UC-NRLF 


B    3    272    D33 


— v 

SIRKfcLEY   \ 

LIBRARY 

UNIVERSITY  OF 
CALIFORNIA      / 


akwctence  A  Na*jr» 


STUDIES 


ANIMAL    LIFE 


GEORGE  HENRY  LEWES, 

AUTHOR  OF  "LIFE  OF  GOETHE,"  "THE  PHYSIOLOGY  OF  COMMON  LIFE,' 
<fcc.,  &c. 


UNI  VIES  ITT 


NEW    YORK: 
HARPER    &    BROTHERS,    PUBLISHERS, 

FBANKLIN     8  Q  U  A  B  E. 
1860. 


81OLOGY 
UBRARY 

G 


CONTENTS. 


CHAPTER  I. 

Omnipresence  of  Life. — The  Microscope. — An  Opalina  and  its 
Wonders. — The  Uses  of  Cilia. — How  our  Lungs  are  protected 
from  Dust  and  Filings. — Feeding  without  a  Mouth  or  Stomach. 
— What  is  an  Organ? — How  a  complex  Organism  arises. — 
Early  Stages  of  a  Frog  and  a  Philosopher. — How  the  Plants 
feed. — Parasites  of  the  Frog. — Metamorphoses  and  Migrations 
of  Parasites. — Life  within  Life. — The  budding  of  Animals. — 
— A  steady  Bore. — Philosophy  of  the  infinitely  little Page  9 

CHAPTER  H.  . 

Ponds  and  Rock-pools. — Our  necessary  Tackle. —  Wimbledon 
Common.  —  Early  Memories. —  Gnat  Larvae. —  Entomostraca 
and  their  Paradoxes. — Races  of  Animals  dispensing  with  the 
sterner  Sex. — Insignificance  of  Males. — Volvox  Globator:  is  it 
an  Animal? — Plants  swimming  like  Animals. — Animal  Retro- 
gressions.— The  Dytiscus  and  its  Larva. — The  Dragon-fly  Lar- 
va.— Mollusks  and  their  Eggs. — Polypes,  and  how  to  find  them. 
— A  new  Polype,  Hydra  rubra. — Nest-building  Fish. — Con- 
tempt replaced  by  Reverence 39 

CHAPTER  m. 

A  garden  Wall,  and  its  Traces  of  past  Life.— Not  a  Breath  per- 
ishes.— A  Bit  of  dry  Moss  and  its  Inhabitants. — The  "Wheel- 
bearers." —  Resuscitation  of  Rotifers:  drowned  into  Life. — 
Current  Belief  that  Animals  can  be  revived  after  complete  De- 
siccation.— Experiments  contradicting  the  Belief. — Spallanzani's 
Testimony. — Value  of  Biology  as  a  Means  of  Culture. — Classi- 
fication of  Animals:  the  five  great  Types. — Criticism  of  Cu- 
vier's  Arrangement 59 


Vlll  CONTENTS. 

CHAPTER  IV. 

An  extinct  Animal  recognized  by  its  Tooth  :  how  came  this  to  be 
possible  ? — The  Task  of  Classification. — Artificial  and  natural 
Methods. — Linnaeus,  and  his  Baptism  of  the  Animal  Kingdom : 
his  Scheme  of  Classification. — What  is  there  underlying  all 
true  Classification  ? — The  chief  Groups. — What  is  a  Species  ? — 
Eestatement  of  the  Question  respecting  the  Fixity  or  Variability 
of  Species. — The  two  Hypotheses. — Illustration  drawn  from  the 
Romance  Languages. — Caution  to  Disputants Page  86 

CHAPTER  V. 

Talking  in  Beetles. — Identity  of  Egyptian  Animals  with  those  now 
existing :  Does  this  prove  Fixity  of  Species  ? — Examination  of 
the  celebrated  Argument  of  Species  not  having  altered  in  four 
thousand  Years. — Impossibility  of  distinguishing  Species  from 
Varieties. — The  Affinities  of  Animals. — New  Facts  proving  the 
Fertility  of  Hybrids. — The  Hare  and  the  Rabbit  contrasted. — 
Doubts  respecting  the  Development  Hypothesis. — On  Hypoth- 
esis in  Natural  History. — Pliny,  and  his  Notion  on  the  Forma- 
tion of  Pearls. — Are  Pearls  owing  to  a  Disease  of  the  Oyster? — 
Formation  of  the  Shell;  Origin  of  Pearls. — How  the  Chinese 
manufacture  Pearls 107 

CHAPTER  VI. 

Every  Organism  a  Colony. — What  is  a  Paradox  ? — An  Organ  is 
an  independent  Individual  and  a  dependent  one. — A  Branch 
of  Coral. — A  Colony  of  Polypes. — The  Siphonophora. — Uni- 
versal Dependence. — Youthful  Aspirings. — Our  Interest  in  the 
Youth  of  great  Men. — Genius  and  Labor. — Cuvier's  College 
Life ;  his  Appearance  in  Youth  ;  his  Arrival  in  Paris. — Cuvier 
and  Geoffrey  St.Hilaire. — Causes  of  Cuvier's  Success. — One  of 
his  early  Ambitions. — M.  le  Baron. — Omnia  vincit  labor. — Con- 
clusion   128 


STUDIES  IN  ANIMAL  LIFE 


CHAPTER  I. 

Omnipresence  of  Life. — The  Microscope. — An  Opalina  and  its 
Wonders. — The  Uses  of  Cilia. — How  our  Lungs  are  protected 
from  Dust  and  Filings. — Feeding  without  a  Mouth  or  Stomach. 
— What  is  an  Organ? — How  a  complex  Organism  arises. — 
Early  Stages  of  a  Frog  and  a  Philosopher. — How  the  Plants 
feed. — Parasites  of  the  Frog. — Metamorphoses  and  Migrations 
of  Parasites. — Life  within  Life. — The  budding  of  Animals. — 
— A  steady  Bore. — Philosophy  of  the  infinitely  little. 

COME  with  me,  and  lovingly  study  Nature,  as  she 
breathes,  palpitates,  and  works  under  myriad  forms 
of  Life — forms  unseen,  unsuspected,  or  unheeded 
by  the  mass  of  ordinary  men.  Our  course  may  be 
through  park  and  meadow,  garden  and  lane,  over 
the  swelling  hills  and  spacious  heaths,  beside  the 
running  and  sequestered  streams,  along  the  tawny 
coast,  out  on  the  dark  and  dangerous  reefs,  or  under 
dripping  caves  and  slippery  ledges.  It  matters  lit- 
tle where  we  go:  every  where — in  the  air  above, 
the  earth  beneath,  and  waters  under  the  earth — we 
are  surrounded  with  Life.  Avert  your  eyes  a  while 
from  our  human  world,  with  its  ceaseless  anxieties, 
its  noble  sorrow,  poignant,  yet  sublime,  of  conscious 
imperfection  aspiring  to  higher  states,  and  contem- 
A2 


10  STUDIES  IN  ANIMAL  LIFE. 

plate  the  calmer  activities  of  that  other  world  with 
which  we  are  so  mysteriously  related.  I  hear  you 
exclaim, 

"The  proper  study  of  mankind  is  man ;" 

nor  will  I  pretend,  as  some  enthusiastic  students 
seem  to  think,  that 

"The  proper  study  of  mankind  is  cells;" 

but  agreeing  with  you,  that  man  is  the  noblest 
study,  I  would  suggest  that  under  the  noblest  there 
are  other  problems  which  we  must  not  neglect. 
Man  himself  is  imperfectly  known,  because  the  laws 
of  universal  Life  are  imperfectly  known.  His  life 
forms  but  one  grand  illustration  of  Biology — the 
science  of  Life,*  as  he  forms  but  the  apex  of  the 
animal  world. 

Our  studies  here  will.be  of  Life,  and  chiefly  of 
those  minuter  or  obscurer  forms,  which  seldom  at- 
tract attention.  In  the  air  we  breathe,  in  the  water 
we  drink,  in  the  earth  we  tread  on,  Life  is  every 
where.  Nature  lives:  every  pore  is  bursting  with 
Life ;  every  death  is  only  a  new  birth,  every  grave 
a  cradle.  And  of  this  we  know  so  little,  think  so 
little !  Around  us,  above  us,  beneath  us,  that  great 
mystic  drama  of  creation  is  being  enacted,  and  we 
will  not  even  consent  to  be  spectators!  Unless 
animals  are  obviously  useful  or  obviously  hurtful 

*  The  needful  term  Biology  (from  Bios,  life,  and  logos,  dis- 
course) is  now  becoming  generally  adopted  in  England,  as  in  Ger- 
many. It  embraces  all  the  separate  sciences  of  Botany,  Zoology, 
Comparative  Anatomy,  and  Physiology. 


STUDIES  IN  ANIMAL   LIFE.  11 

to  us,  we  disregard  them.  Yet  they  are  not  alien, 
but  akin.  The  Life  that  stirs  within  us  stirs  with- 
in them.  We  are  all  "parts  of  one  transcendent 
whole."  The  scales  fall  from  our  eyes  when  we 
think  of  this ;  it  is  as  if  a  new  sense  had  been  vouch- 
safed to  us,  and  we  learn  to  look  at  Nature  with  a 
more  intimate  and  personal  love. 

Life  every  where !  The  air  is  crowded  with  birds 
~— beautiful,  tender,  intelligent  birds — to  whom  life 
is  a  song  and  a  thrilling  anxiety,  the  anxiety  of 
love.  The  air  is  swarming  with  insects — those  lit- 
tle animated  miracles.  The  waters  are  peopled 
with  innumerable  forms,  from  the  animalcule,  so 
small  that  one  hundred  and  fifty  millions  of  them 
would  not  weigh  a  grain,  to  the  whale,  so  large 
that  it  seems  an  island  as  it  sleeps  upon  the  waves. 
The  bed  of  the  seas  is  alive  with  polypes,  crabs, 
star-fishes,  and  with  sand-numerous  shell-animal- 
cules. The  rugged  face  of  rocks  is  scarred  by  the 
silent  boring  of  soft  creatures,  and  blackened  with 
countless  mussels,  barnacles,  and  limpets. 

Life  every  where !  on  the  earth,  in  the  earth, 
crawling,  creeping,  burrowing,  boring,  leaping,  run- 
ning. If  the  sequestered  coolness  of  the  wood  tempt 
us  to  saunter  into  its  checkered  shade,  we  are  sa- 
luted by  the  murmurous  din  of  insects,  the  twitter 
of  birds,  the  scrambling  of  squirrels,  the  startled 
rush  of  unseen  beasts,  all  telling  how  populous  is 
this  seeming  solitude.  If  we  pause  before  a  tree, 
or  shrub,  or  plant,  our  cursory  and  half-abstracted 


12  STUDIES  IN  ANIMAL  LIFE. 

glance  detects  a  colony  of  various  inhabitants.  We 
pluck  a  flower,  and  in  its  bosom  we  see  many  a 
charming  insect  busy  at  its  appointed  labor.  We 
pick  up  a  fallen  leaf,  and  if  nothing  is  visible  on  it, 
there  is  probably  the  trace  of  an  insect  larva  hidden 
in  its  tissue,  and  awaiting  there  development.  The 
drop  of  dew  upon  this  leaf  will  probably  contain 
its  animals,  visible  under  the  microscope.  This 
same  microscope  reveals  that  the  Hood-rain  sudden- 
ly appearing  on  bread,  and  awakening  superstitious 
terrors,  is  nothing  but  a  collection  of  minute  ani- 
mals (Monas  prodigiosa) ;  and  that  the  vast  tracts 
of  snow  which  are  reddened  in  a  single  night  owe 
their  color  to  the  marvelous  rapidity  in  reproduc- 
tion of  a  minute  plant  (Protococcus  nivalis).  The 
very  mould  which  covers  our  cheese,  our  bread,  our 
jam,  or  our  ink,  and  disfigures  our  damp  walls,  is 
nothing  but  a  collection  of  plants.  The  many-col- 
ored fire  which  sparkles  on  the  surface  of  a  summer 
sea  at  night,  as  the  vessel  plows  her  way,  or  which 
drips  from  the  oars  in  lines  of  jeweled  light,  is  pro- 
duced by  millions  of  minute  animals. 

Nor  does  the  vast  procession  end  here.  Our  very 
mother-earth  is  formed  of  the  debris  of  life.  Plants 
and  animals  which  have  been  build  up  its  solid 
fabric.*  We  dig  downward  thousands  of  feet  be- 
low the  surface,  and  discover  with  surprise  the 

*  See  EHRENBERG:  Microgeologie :  das  Erden  und  Felsen 
schaffende  Wirken  des  unsichtbar  kleinen  selbststandigen  Lebcns  auf 
der  Erde.  1854. 


STUDIES  IN   ANIMAL   LIFE.  13 

skeletons  of  strange,  uncouth  animals,  which  roamed 
the  fens  and  struggled  through  the  woods  before 
man  was.  Our  surprise  is  heightened  when  we 
learn  that  the  very  quarry  itself  is  mainly  com- 
posed of  the  skeletons  of  microscopic  animals ;  the 
flints  which  grate  beneath  our  carriage  wheels  are 
but  the  remains  of  countless  skeletons.  The  Apen- 
nines and  Cordilleras,  the  chalk  cliffs  so  dear  to 
homeward-nearing  eyes — these  are  the  pyramids  of 
by-gone  generations  of  atomies.  Ages  ago  these 
tiny  architects  secreted  the  tiny  shells  which  were 
their  palaces ;  from  the  ruins  of  these  palaces  we 
build  our  Parthenons,  our  St.  Peters,  and  our  Lou- 
vres. So  revolves  the  luminous  orb  of  Life !  Gen- 
erations follow  generations;  and  the  Present  be- 
comes the  matrix  of  the  Future,  as  the  Past  was  of 
the  Present — the  Life  of  one  epoch  forming  the  pre- 
lude to  a  higher  Life. 

"When  we  have  thus  ranged  air,  earth,  and  water, 
rinding  every  where  a  prodigality  of  living  forms, 
visible  and  invisible,  it  might  seem  as  if  the  survey 
were  complete.  And  yet  it  is  not  so.  Life  cradles 
within  Life.  The  bodies  of  animals  are  little  worlds, 
having  their  own  animals  and  plants.  A  celebrated 
Frenchman  has  published  a  thick  octavo  volume 
devoted  to  the  classification  and  description  of  "The 
Plants  which  grow  on  Men  and  Animals;"*  and 
many  Germans  have  described  the  immense  variety 

*  CHARLES  EOBIN  :  Histoire  Naturelle  des  Vegetaux  Parasites 
qui  croissent  sur  VHomme  et  sur  les  Animaux  Vivants.  1853. 

A* 


14  STUDIES   IN   ANIMAL   LIFE. 

of  animals  which  grow  on  and  in  men  and  animals ; 
so  that  science  can  now  boast  of  a  parasitic  Flora 
and  Fauna.  In  the  fluids  and  tissues,  in  the  eye, 
in  the  liver,  in  the  stomach,  in  the  brain,  in  the 
muscles,  parasites  are  found,  and  these  parasites 
have  often  their  parasites  living  in  them ! 

We  have  thus  taken  a  bird's-eye  view  of  the  field 
in  which  we  may  labor.  It  is  truly  inexhaustible. 
We  may  begin  where  we  please,  we  shall  never 
come  to  an  end ;  our  curiosity  will  never  slacken. 

"  And  whosoe'er  in  youth 
Has  through  ambition  of  his  soul  given  way 
To  such  desires,  and  grasp'd  at  such  delights, 
Shall  feel  congenial  stirrings  late  and  long." 

As  a  beginning,  get  a  microscope.  If  you  can  not 
borrow,  boldly  buy  one.  Few  purchases  will  yield 
you  so  much  pleasure ;  and,  while  you  are  about  it, 
do,  if  possible,  get  a  good  one.  Spend  as  little 
money  as  you  can  on  accessory  apparatus  and  ex- 
pensive fittings,  but  get  a  good  stand  and  good 
glasses.  Having  got  your  instrument,  bear  in  mind 
these  two  important  trifles — work  by  daylight,  sel- 
dom or  never  by  lamplight ;  and  keep  the  unoccu- 
pied eye  open.  With  these  precautions  you  may 
work  daily  for  hours  without  serious  fatigue  to  the 
eye. 

Now  where  shall  we  begin?  Any  where  will 
do.  This  dead  frog,  for  example,  that  has  already 
been  made  the  subject  of  experiments,  and  is  now 
awaiting  the  removal  of  its  spinal  cord,  will  serve 


STUDIES  IN   ANIMAL   LIFE. 


15 


us  as  a  text  from  which  profitable  lessons  may  be 
drawn.  We  snip  out  a  portion  of  its  digestive  tube, 
which,  from  its  emptiness,  seems  to  promise  little  ; 
but  a  drop  of  the  liquid  we  find  in  it  is  placed  on 
a  glass  slide,  covered  with  a  small  piece  of  very- 
thin  glass,  and  brought  under  the  microscope.  Now 
look.  There  are  several  things  which  might  occu- 
py your  attention,  but  dis- 
regard them  now  to  watch 
that  animalcule  which  you 
observe  swimming  about. 
What  is  it  ?  It  is  one  of  the 
largest  of  the  Infusoria,  and 
is  named  Opalina.  When 
I  call  this  an  Infusorium  I 
am  using  the  language  of 
text-books  ;  but  there  seems 
to  be  a  growing  belief  among 
zoologists  that  the  Opalina 

ig  not  an  Infusorium,  but  the 
.  . 

infantile  condition  of  some 
worm  -(Distoma  T).  However,  it  will  not  grow  into 
a  mature  worm  as  long  as  it  inhabits  the  frog; 
it  waits  till  some  pike  or  bird  has  devoured  the 
frog,  and  then,  in  the  stomach  of  its  new  captor,  it 
will  develop  into  its  mature  form  —  then,  and  not 
till  then.  This  surprises  you.  And  well  it  may; 
but  thereby  hangs  a  tale,  which  to  unfold  —  for  the 
present,  however,  it  must  be  postponed,  because  the 
Opalina  itself  needs  all  our  notice. 


Fig.  I.-OPALINA  EAXAKTTM. 
A,  front  view;  R,  side  view  —  mag- 


16  STUDIES   IN   ANIMAL   LIFE. 

Obser.e  how  transparent  it  is,  and  with  what 
easy,  undulating  grace  it  swims  about;  yet  this 
swimmer  has  no  arms,  no  legs,  no  tail,  no  backbone 
to  serve  as  a  fulcrum  to  moving  muscles — nay,  it  has 
no  muscles  to  move  with.  'Tis  a  creature  of  the 
most  absolute  abnegations — sans  eyes,  sans  teeth, 
sans  every  thing ;  no,  not  sans  every  thing,  for,  as 
we  look  attentively,  we  see  certain  currents  pro- 
duced in  the  liquid,  and,  on  applying  a  higher  mag- 
nifying power,  we  detect  how  these  currents  are 
produced.  All  over  the  surface  of  the  Opalina 
there  are  delicate  hairs  in  incessant  vibration ;  these 
are  the  cilia*  They  lash  the  water,  and  the  animal 
is  propelled  by  their  strokes,  as  a  galley  by  its  hund- 
red oars.  This  is  your  first  sight  of  that  ciliary  ac- 
tion of  which  you  have  so  often  read,  and  which 
you  will  henceforth  find  performing  some  important 
service  in  almost  every  animal  you  examine.  Some- 
times the  cilia  act  as  instruments  of  locomotion; 
sometimes  as  instruments  of  respiration,  by  contin- 
ually renewing  the  current  of  water ;  sometimes  as 
the  means  of  drawing  in  food,  for  which  purpose 
they  surround  the  mouth,  and  by  their  incessant 
action  produce  a  small  whirlpool  into  which  the 
food  is  sucked.  An  example  of  this  is  seen  in  the 
Yorticella.  (Fig.  2.) 

Having  studied  the  action  of  these  cilia  in  micro- 
scopic animals,  you  will  be  prepared  to  understand 
their  office  in  your  own  organism.  The  lining 

*  From  ciliwn,  a  hair. 


STUDIES   IN   ANIMAL   LIFE. 
Fig.  2. 


17 


GEOTIP  OP  VOBTICELLA  NEBUIJFEKA  on  a  Stem  of  Weed,  magnified. 

A,  one  undergoing  spontaneous  division ;  B,  another  spirally  retracted  on  its 
stalk ;  C,  one  with  cilia  refracted ;  D,  a  bud  detached  and  swimming  free. 

membrane  of  your  air-passages  is  covered  with  cilia, 
which  may  be  observed  by  following  the  directions 
of  Professor  Sharpey,  to  whom  science  is  indebted 
for  a  very  exhaustive  description  of  these  organs. 
"  To  see  them  in  motion,  a  portion  of  the  ciliated 
mucous  membrane  may  be  taken  from  a  recently- 
killed  quadruped.  The  piece  of  membrane  is  to  be 
folded  with  its  free,  or  ciliated  surface  outward, 
placed  on  a  slip  of  glass,  with  a  little  water  or  serum 
of  blood,  and  covered  with  thin  glass  or  mica. 
When  it  is  now  viewed  with  a  power  of  200  diam- 


18  STUDIES  IN  ANIMAL   LIFE. 

eters  or  upward,  a  very  obvious  agitation  will  be 
perceived  on  the  edge  of  the  fold,  and  this  appear- 
ance is  caused  by  the  moving  cilia  with  which  the 
surface  of  the  membrane  is  covered.  Being  set 
close  together,  and  moving  simultaneously  or  in 
quick  succession,  the  cilia,  when  in  brisk  action, 
give  rise  to  the  appearance  of  a  bright  transparent 
fringe  along  the  fold  of  the  membrane,  agitated  by 
such  a  rapid  and  incessant  motion  that  the  single 
threads  which  compose  it  can  not  be  perceived. 
The  motion  here  meant  is  that  of  the  cilia  them- 
selves; but  they  also  set  in  motion  the  adjoining 
fluid,  driving  it  along  the  ciliated  surface,  as  is  in- 
dicated by  the  agitation  of  any  little  particles  that 
may  accidentally  float  in  it.  The  fact  of  the  con- 
veyance of  fluids  and  other  matters  along  the  cili- 
ated surface,  as  well  as  the  direction  in  which  they 
are  impelled,  may  also  be  made  manifest  by  im- 
mersing the  membrane  in  fluid,  and  dropping  on  it 
some  finely -pulverized  substance  (such  as  charcoal 
in  fine  powder),  which  will  be  slowly  but  steadily 
carried  along  in  a  constant  and  determinate  direc- 
tion."* 

It  is  an  interesting  fact,  that  while  the  direction 
in  which  the  cilia  propel  fluids  and  particles  is  gen- 
erally toward  the  interior  of  the  organism,  it  is 
sometimes  reversed,  and,  instead  of  beating  the  par- 

*  Quoin's  Anatomy.  By  SHAEPEY  and  ELLIS.  Sixth  edition. 
I.,  p.  Ixxiii.  See  also  SHARPEY'S  article  Cilia,  in  the  Cyclopaedia 
of  Anatomy  and  Physiology. 


STUDIES   IN  ANIMAL  LIFE.  19 

tides  inward,  the  cilia  energetically  beat  them  back 
if  they  attempt  to  enter.  Fatal  results  would  ensue 
if  this  were  not  so.  Our  air-passages  would  no 
longer  protect  the  lungs  from  particles  of  sand,  coal- 
dust,  and  filings  flying  about  the  atmosphere ;  on 
the  contrary,  the  lashing  hairs  which  cover  the  sur- 
face of  these  passages  would  catch  up  every  parti- 
cle,, and  drive  it  onward  into  the  lungs.  Fortunate- 
ly for  us,  the  direction  of  the  cilia  is  reversed,  and 
they  act  as  vigilant  janitors,  driving  back  all  va- 
grant particles  with  a  stern  "  No  admittance,  even 
on  business !"  In  vain  does  the  whirlwind  dash  a 
column  of  dust  in  our  faces — in  vain  does  the  air, 
darkened  with  coal-dust,  impetuously  rush  up  the 
nostrils ;  the  air  is  allowed  to  pass  on,  but  the  dust 
is  inexorably  driven  back.  Were  it  not  so,  how 
could  miners,  millers,  iron- workers,  and  all  the  mod- 
ern Tubal  Cains  contrive  to  live  in  their  loaded 
atmospheres?  In  a  week  their  lungs  would  be 
choked  up. 

Perhaps  you  will  tell  me  that  this  is  the  case — 
that  manufacturers  of  iron  and  steel  are  very  subject 
to  consumption,  and  that  there  is  a  peculiar  discol- 
oration of  the  lungs  which  has  often  been  observed 
in  coal-miners  examined  after  death. 

Not  being  a  physican,  and  not  intending  to  trouble 
you  with  medical  questions,  I  must  still  place  be- 
fore you  three  considerations,  which  will  show  how 
untenable  this  notion  is.  First,  although  consump- 
tion may  be  frequent  among  the  Sheffield  workmen. 


20  STUDIES  IN   ANIMAL   LIFE. 

the  cause  is  not  to  be  sought  in  their  breathing 
filings,  but  in  the  sedentary  and  unwholesome  con- 
finement incidental  to  their  occupation.  Miners 
and  coal-heavers  are  not  troubled  with  ,consump- 
tion.  Moreover,  if  the  filings  were  the  cause,  all 
the  artisans  would  suffer,  when  all  breathe  the  same 
atmosphere.  Secondly,  while  it  is  true  that  dis- 
colored lungs  have  been  observed  in  some  miners, 
it  has  not  been  observed  in  all  or  in  many ;  where- 
as it  has  been  observed  in  men  not  miners,  not  ex- 
posed to  any  unusual  amount  of  coal-dust.  Third- 
ly, and  most  conclusively,  experiment  has  shown 
that  the  coal-dust  can  not  penetrate  to  the  lungs. 
Claude  Bernard,  the  brilliant  experimenter,  tied  a 
bladder  containing  a  quantity  of  powdered  char- 
coal to  the  muzzle  of  a  rabbit.  Whenever  the  an- 
imal breathed,  the  powder  within  the  bladder  was 
seen  to  be  agitated.  Except  during  feeding-time 
the  bladder  was  kept  constantly  on,  so  that  the 
animal  breathed  only  this  dusty  air.  If  the  powder 
could  have  escaped  the  vigilance  of  the  cilia  and 
got  into  the  lungs,  this  was  a  good  occasion.  But 
when  the  rabbit  was  killed  and  opened,  many  days 
afterward,  no  powder  whatever  was  found  in  the 
lungs  or  bronchial  tubes ;  several  patches  were  col- 
lected about  the  nostrils  and  throat,  but  the  cilia 
had  acted  as  a  strainer,  keeping  all  particles  from 
the  air-tubes. 

The  swimming  apparatus  of  the  Opalina  has  led 
us  far  away  from  the  little  animal  who  has  been 


STUDIES   IN   ANIMAL   LIFE.  21 

feeding  while  we  have  been  lecturing.  At  the  men- 
tion of  feeding  you  naturally  look  for  the  food  that 
is  eaten,  the  mouth  and  stomach  that  eat.  But  I 
hinted  just  now  that  this  ethereal  creature  dispenses 
with  a  stomach,  as  too  gross  for  its  nature,  and  of 
course,  by  a  similar  refinement,  dispenses  with  a 
mouth.  Indeed,  it  has  no  organs  whatever  except 
the  cilia  just  spoken  of.  The  same  is  true  of  several 
of  the  Infusoria,  for  you  must  know  that  naturalists 
no  longer  recognize  the  complex  organization  which 
Ehrenberg  fancied  he  had  detected  in  these  micro- 
scopic beings.  If  it  pains  you  to  relinquish  the 
piquant  notion  of  a  microscopic  animalcule  having 
a  structure  equal  in  complexity  to  that  of  the  ele- 
phant, there  will  be  ample  compensation  in  the 
notion  which  replaces  it,  the  notion  of  an  ascending 
series  of  animal  organisms,  rising  from  the  struc- 
tureless amoeba  to  the  complex  frame  of  a  mammal. 
On  a  future  occasion  we  shall  see  that,  great  as 
Ehrenberg's  services  have  been,  his  interpretations 
of  what  he  saw  have  one  by  one  been  replaced  by 
truer  notions.  His  immense  class  of  Infusoria  has 
been,  and  is  constantly  being,  diminished;  many 
of  his  animals  turn  out  to  be  plants ;  many  of  them 
embryos  of  worms ;  and  some  of  them  belong  to 
the  same  divisions  of  the  animal  kingdom  as  the 
oyster  and  the  shrimp — that  is  to  say,  they  range 
with  the  Mollusks  and  Crustaceans.  In  these,  of 
course,  there  is  a  complex  organization ;  but  in  the 
Infusoria,  as  now  understood,  the  organization  is 


22  STUDIES   IN   ANIMAL   LIFE. 

extremely  simple.  No  one  now  believes  the  clear 
spaces  visible  in  their  substance  to  be  stomachs,  as 
Ehrenberg  believed ;  and  the  idea  of  the  Polygas- 
trica,  or  many-stomached  Infusoria,  is  abandoned. 
No  one  now  believes  the  colored  specs  to  be  eyes, 
because,  not  to  mention  the  difficulty  of  conceiving 
eyes  where  there  is  no  nervous  system,  it  has  been 
found  that  even  the  spores  of  some  plants  have 
these  colored  specs,  and  they  are  assuredly  not  eyes. 
If,  then,  we  exclude  the  highly-organized  Ratifera, 
or  "Wheel  Animalcules,"  which  are  genuine  Crus- 
tacea, we  may  say  that  all  Infusoria,  whether  they 
be  the  young  of  worms  or  not,  are  of  very  simple 
organization. 

And  this  leads  us  to  consider  what  biologists 
mean  by  an  organ :  it  is  a  particular  portion  of  the 
body  set  apart  for  the  performance  of  some  particu- 
lar function.  The  whole  process  of  development  is 
this  setting  apart  for  special  purposes.  The  start- 
ing-point of  Life  is  a  single  cell — that  is  to  say,  a 
microscopic  sac,  filled  with  liquid  and  granules,  and 
having  within  it  a.  nucleus,  or  smaller  sac.  Paley 
has  somewhere  remarked  that  in  the  early  stages 
there  is  no  difference  discernible  between  a  frog  and 
a  philosopher.  It  is  very  true — truer  than  he  con- 
ceived. In  the  earliest  stage  of  all,  both  the  Ba- 
trachian  and  the  Philosopher  are  nothing  but  single 
cells,  although  the  one  cell  will  develop  into  an 
Aristotle  or  a  Newton,  and  the  other  will  get  no 
higher  than  the  cold,  damp,  croaking  animal  which 


STUDIES  IN   ANIMAL   LIFE.  23 

boys  will  pelt,  anatomists  dissect,  and  Frenchmen 
eat.  From  the  starting-point  of  a  single  cell  this 
is  the  course  taken :  the  cell  divides  itself  into  two, 
the  two  become  four,  the  four  eight,  and  so  on,  till 
a  mass  of  cells  is  formed  not  unlike  the  shape  of 
a  mulberry.  This  mulberry-mass  then  becomes  a 
sac,  with  double  envelopes  or  walls ;  the  inner  wall, 
turned  toward  the  yelk,  or  food,  becomes  the  assim- 
ilating surface  for  the  whole ;  the  outer  wall,  turned 
toward  the  surrounding  medium,  becomes  the  sur- 
face which  is  to  bring  frog  and  philosopher  into 
contact  and  relation  with  the  external  world — the 
Non-Ego,  as  the  philosopher  in  after  life  will  call  it. 
Here  we  perceive  the  first  grand  "  setting  apart,"  or 
differentiation,  has  taken  place ;  the  embryo  having 
an  assimilating  surface,  which  has  little  to  do  with 
the  external  world,  and  a  sensitive,  contractile  sur- 
face, which  has  little  to  do  with  the  preparation  and 
transport  of  food.  The  embryo  is  no  longer  a  mass 
of  similar  cells ;  it  is  already  become  dissimilar,  dif- 
ferent, as  respects  its  inner  and  outer  envelope. 
But  these  envelopes  are  at  present  uniform;  one 
part  of  each  is  exactly  like  the  rest.  Let  us,  there- 
fore, follow  the  history  of  Development,  and  we 
shall  find  that  the  inner  wall  gradually  becomes  un- 
like itself  in  various  parts,  and  that  certain  organs, 
constituting  a  very  complex  apparatus  of  Digestion, 
Secretion,  and  Excretion,  are  all  one  by  one  wrought 
out  of  it  by  a  series  of  metamorphoses  or  differentia- 
tions. The  inner  wall  thus  passes  from  a  simple 


24  STUDIES  Itf  ANIMAL   LIFE. 

assimilating  surface  to  a  complex  apparatus  serving 
the  functions  of  vegetative  life. 

Now  glance  at  the  outer  wall :  from  it  also  vari- 
ous organs  have  gradually  been  wrought ;  it  has  de- 
veloped into  muscles,  nerves,  bones,  organs  of  sense, 
and  brain — all  these  from  a  simple  homogeneous 
membrane ! 

With  this  bird's-eye  view  of  the  course  of  devel- 
opment you  will  be  able  to  appreciate  the  grand 
law  first  clearly  enunciated  by  Goethe  and  Yon 
Baer  as  the  law  of  animal  life,  namely,  that  devel- 
opment is  always  from  the  general  to  the  special, 
from  the  simple  to  the  complex,  from  the  homoge- 
neous to  the  heterogeneous,  and  this  by  a  gradual 
series  of  differentiations*  Or,  to  put  it  into  the 
music  of  our  deeply  meditative  Tennyson, 

"All  nature  widens  upward.    Evermore 

The  simpler  essence  lower  lies : 
More  complex  is  more  perfect — owning  more 
Discourse,  more  widely  wise." 

You  are  now  familiarized  with  the  words  "  differ- 
entiation" and  "development,"  so  often  met  with 
in  modern  writers,  and  have  gained  a  distinct  idea 
of  what  an  "  organ"  is,  so  that,  on  hearing  of  an 
animal  without  organs,  you  will  at  once  conclude 
that  in  such  an  animal  there  has  been  no  setting 
apart  of  any  portion  of  the  body  for  special  pur- 
poses, but  that  all  parts  serve  all  purposes  indis- 

*  GOETHE:  Zur  Morphologic,  1807.  VON  BAER:  ZurEntwick- 
elungsgeschichte,  1 828.  Part  I.,  p.  158. 


OF  THE 
STUDIES  IN  AJSTIMAL  LI^TJ  JJ I  V  H?l  S  I  T  3f 

criminately.  Here  is  our  Qpalina,Nfop'' example, 
without  mouth,  or  stomach,  or  any  other  organ.  It 
is  an  assimilating  surface  in  every  part;  in  every 
part  a  breathing,  sensitive  surface.  Living  on  liquid 
food,  it  does  not  need  a  mouth  to  seize,  or  a  stomach 
to  digest  such  food.  The  liquid,  or  gas,  passes 
through  the  Opalina's  delicate  skin  by  a  process 
which  is  called  endosmosis  ;  it  there  serves  as  food ; 
and  the  refuse  passes  out  again  by  a  similar  process, 
called  exosmosis.  This  is  the  way  in  which  many 
animals  and  all  plants  are  nourished.  The  cell  at 
the  end  of  a  rootlet,  which  the  plant  sends  burrow- 
ing through  the  earth,  has  no  mouth  to  seize,  no 
open  pores  to  admit  the  liquid  that  it  needs ;  never- 
theless, the  liquid  passes  into  the  cell  through  its 
delicate  cell-wall,  and  passes  from  this  cell  to  other 
cells  upward  from  the  rootlet  to  the  bud.  It  is  in 
this  way,  also,  that  the  Opalina  feeds:  it  is  all- 
mouth,  no-mouth ;  all-stomach,  no-stomach.  Every 
part  of  its  body  performs  the  functions  which  in 
more  complex  animals  are  performed  by  organs 
specially  set  apart.  It  feeds  without  mouth,  breathes 
without  lungs,  and  moves  without  muscles. 

The  Opalina,  as  I  said,  is  a  parasite.  It  may  be 
found  in  various  animals,  and  almost  always  in  the 
frog.  You  will  perhaps  ask  why  it  should  be  con- 
sidered a  parasite  ?  why  may  it  not  have  been  swal- 
lowed by  the  frog  in  a  gulp  of  water  ?  Certainly 
nothing  would  have  been  easier.  But,  to  remove 
your  doubts,  I  open  the  skull  of  this  frog,  and  care- 
B 


26 


STUDIES  IN  ANIMAL  LIFE. 


fully  remove  a  drop  of  the  liquid  found  inside, 
which,  on  being  brought  under  a  microscope,  we 
shall  most  probably  find  containing  some  animal- 
cules, especially  those  named  Monads.  These  were 
not  swallowed.  They  live  in  the  cerebro-spinal 
fluid,  as  the  Opalina  lives  in  the  digestive  tube. 
Nay,  if  we  extend  our  researches,  we  shall  find 
that  various  organs  have  their  various  parasites. 
Here,  for  instance,  is  a  parasitic  worm  from  the 

frog's  bladder.  Place  it 
under  the  microscope  with 
a  high  power,  and  behold ! 
It  is  called  Polystomum — 
many-mouthed,  or,  more 
properly,  many-suckered. 
You  are  looking  at  the  un- 
der side,  and  will  observe 
six  large  suckers  with  their 
starlike  clasps  (e),  and  the 
horny  instrument  (/)  with 
which  the  animal  bores  its 
way.  At  a  there  is  anoth- 
er sucker,  which  serves 
also  as  a  mouth ;  at  b  you 
perceive  the  rudiment  of  a 
gullet,  and  at  d  the  repro- 
ductive organs.  But  pay  attention  to  the  pretty 
branchings  of  the  digestive  tube  (c),  which  ramifies 
through  the  body  like  a  blood-vessel. 

This  arrangement  of  the  digestive  tube  is  found 


Fig.  3.—  POLYSTOMUM  INTEGEEEI- 
MTTM,  magnified. 


STUDIES  IN  ANIMAL   LIFE.  27 

in  many  animals,  and  is  often  mistaken  for  a  system 
of  blood-vessels.  In  one  sense  this  is  correct,  for 
these  branching  tubes  are  carriers  of  nutriment,  and 
the  only  circulating  vessels  such  animals  possess ; 
but  the  nutriment  is  chyme,  not  blood :  these  simple 
animals  have  not  arrived  at  the  dignity  of  blood, 
which  is  a  higher  elaboration  of  the  food,  fitted  for 
higher  organisms. 

Thus  may  our  frog,  besides  its  own  marvels,  af- 
ford us  many  "  authentic  tidings  of  invisible  things," 
and  is  itself  a  little  colony  of  life.  Nature  is  eco- 
nomic as  well  as  prodigal  of  space.  She  fills  the  il- 
limitable heavens  with  planetary  and  starry  grand- 
eurs, and  the  tiny  atoms  moving  over  the  crust  of 
earth  she  makes  the  homes  of  the  infinitely  little. 
Far  as  the  mightiest  telescope  can  reach,  it  detects 
worlds  in  clusters,  like  pebbles  on  the  shore  of  in- 
finitude ;  deep  as  the  microscope  can  penetrate,  it 
detects  life  within  life,  generation  within  genera- 
tion, as  if  the  very  universe  itself  were  not  vast 
enough  for  the  energies  of  life ! 

That  phrase,  generation  within  generation,  was 
not  a  careless  phrase ;  it  is  exact.  Take  the  tiny 
insect  (Aphis)  which,  with  its  companions,  crowds 
your  rose-tree ;  open  it,  in  a  solution  of  sugar- water, 
under  your  microscope,  and  you  will  find  in  it  a 
young  insect  nearly  formed ;  open  that  young  in- 
sect with  care,  and  you  will  find  in  it,  also,  another 
young  one,  less  advanced  in  its  development,  but 
perfectly  recognizable  to  the  experienced  eye ;  and 


28  STUDIES  IN  ANIMAL  LIFE. 

beside  this  embryo  you  will  find  many  eggs,  which 
would  in  time  become  insects ! 

Or  take  that  lazy  water-snail  (Paludina  vivipara\ 
first  made  known  to  ^science  by  the  great  Swam- 
merdamm,  the  incarnation  of  patience  and  exact- 
ness, and  you  will  find,  as  he  found,  forty  or  fifty 
young  snails  in  various  stages  of  development ;  and 
you  will  also  find,  as  he  found,  some  tiny  worms, 
which,  if  you  cut  them  open,  will  suffer  three  or 
four  infusoria  to  escape  from  the  opening.*  In  your 
astonishment  you  will  ask,  "Where  is  this  to  end  ? 

The  observation  recorded  by  Swammerdamm, 
like  so  many  others  of  this  noble  worker,  fell  into 
neglect,  but  modern  investigators  have  made  it  the 
starting-point  of  a  very  curious  inquiry.  The  worms 
he  found  within  the  snail  are  now  called  Cercaria 
sacs,  because  they  contain  the  Cercarice,  once  classed 
as  Infusoria,  and  which  are  now  known  to  be  the 
early  forms  of  parasitic  worms  inhabiting  the  di- 
gestive tube  and  other  cavities  of  higher  animals. 
These  Cercarice  have  vigorous  tails,  with  which  they 
swim  through  the  water  like  tadpoles,  and,  like  tad- 
poles, they  lose  their  tails  in  after  life.  But  how, 
think  you,  did  these  sacs  containing  Cercarice  get 
into  the  water-snails?  "By  spontaneous  genera- 
tion," formerly  said  the  upholders  of  that  hypothe- 
sis, and  those  who  condemned  the  hypothesis  were 
forced  to  admit  they  had  no  better  explanation.  It 
was  a  mystery  which  they  preferred  leaving  unex- 

*  SWAMMERDAMM.     Bibel  der  Natur,  p.  75-77. 


STUDIES  IN  ANIMAL  LIFE.  29 

plained  rather  than  fly  to  spontaneous  generation. 
And  they  were  right.  The  mystery  has  at  length 
been  cleared  up.*  I  will  endeavor  to  bring  togeth- 
er the  scattered  details,  and  narrate  the  curious 
story. 

Under  the  eyelids  of  geese  and  ducks  may  be 
constantly  found  a  parasitic  worm  (of  the  Trematode 
order),  which  naturalists  have  christened  Monosto- 
mum  mutdbile— Single-mouth,  Changeable.  This 
worm  brings  forth  living  young,  in  the  likeness  of 
active  Infusoria,  which,  being  covered  with  cilia, 
swim  about  in  the  water  as  we  saw  the  Opalina 
swim.  Here  is  a  portrait  of  one. 


Fig.  4 — A,  EMBBYO  OP  MONOSTOMTJM  MUTABLLE. 
B,  Cercaria  sac,  just  set  free. 

a,  mouth;  6,  pigment  spots;  c,  sac — magnified. 

Each  of  these  animalcules  develops  a  sac  in  its 
interior.  The  sac  you  may  notice  in  the  engraving. 

*  By  VON  SIEBOLD.  See  his  interesting  work,  Ueber  die  Band- 
und-Blasenwilrmer .  It  has  been  translated  by  HUXLEY,  and  ap- 
pended to  the  translation  of  KUECHENMEISTER  on  Parasites,  pub- 
lished by  the  Sydenham  Society. 


30 


STUDIES  IN  ANIMAL   LIFE. 


Having  managed  to  get  into  the  body  of  the  water- 
snail,  the  animalcule's  part  in  the  drama  is  at  an 
end.  It  dies,  and  in  dying  liberates  the  sac,  which 
is  very  comfortably  housed  and  fed 
by  the  snail.  If  you  examine  this  sac 
(Fig.  5),  you  will  observe  that  it  has 
a  mouth  and  digestive  tube,  and  is, 
therefore,  very  far  from  being,  what  its 
name  imports,  a  mere  receptacle ;  it  is 
an  independent  animal,  and  lives  an 
independent  life.  It  feeds  generously 

Fig.  5.— CEBCABIA  ,       .     .  „    ,  .,  -,    , 

SAC.          on  the  juices  of  the  snail,  and, -having 
fed,  thinks  generously  of  the  coming 
generations.     It  was  born  inside  the 
different  Stages  animalcule ;  why  should  it  not  in  turn 
give  birth  to  children  of  its  own  ?     To 
found  a  dynasty,  to  scatter  progeny  over  the  boun- 
teous earth,  is  a  worthy  ambition.     The  mysterious 
agency  of  reproduction  begins  in 
this  sac-animal,  and  in  a  short 
while  a  brood  of  Cercarice  move 
within  it.     The  sac  bursts,  and 
the  brood  escapes.     But  how  is 
this?     The  children  are  by  no 
means  the  "  very  image"  of  their 
parent.     They  are  not  sacs,  nor 
in  the  least  resembling  sacs,  as 
you  see  (Fig.  6). 

They  have  tails,  and  suckers, 
and  sharp  boring  instruments, 


Fig.  6. — CERCABIA  DEVEL- 
OPED. 

A,  mouth;  B,  B,  B,  excre- 
tory organ;  C,  pigment 
spots ;  D,  tail. 


STUDIES  1ST  ANIMAL  LIFE.  31 

with  other  organs  which  their  parent  was  without. 
To  look  at  them  you  would  as  soon  suspect  a  shrimp 
to  be  the  progeny  of  an  oyster,  as  these  to  be  the 
progeny  of  the  sac-animal.  And  what  makes  the 
paradox  more  paradoxical  is,  that  not  only  are  the 
Cercarios,  unlike  their  parent,  but  their  parent  was 
equally  unlike  its  parent,  the.  embryo  of  Monosto- 
mum  (compare  Fig.  4).  However,  if  we  pursue  this 
family  history,  we  shall  find  the  genealogy  rights 
itself  at  last,  and  that  this  Cercaria  will  develop  in 
the  body  of  some  bird  into  a  Monostomum  mutdbile 
like  its  ancestor.  Thus  the  worm  produces  an  an- 
imalcule, which  produces  a  sac-animal,  which  pro- 
duces a  Cercaria,  which  becomes  a  worm  exactly 
resembling  its  great-grandfather. 

One  peculiarity  in  this  history  is,  that  while  the 
Monostomum  produces  its  young  in  the  usual  way, 
the  two  intermediate  forms  are  produced  by  a  process 
of  budding  analogous  to  that  observed  in  plants. 
Plants,  as  you  know,  are  reproduced  in  two  ways 
• — from  the  seed  and  from  the  bud.  For  seed- 
reproduction  peculiar  organs  are  necessary;  for 
bud-reproduction  there  is  no  such  differentiation 
needed:  it  is  simply  an  outgrowth.  The  same  is 
true  of  many  animals ;  they  also  bud  like  plants, 
and  produce  seeds  (eggs)  like  plants.  I  have  else- 
where argued  that  the  two  processes  are  essentially 
identical,  and  that  both  are  but  special  forms  of 
growth.*  Not,  however,  to  discuss  so  abstruse  a 

*  Seaside  Studies,  p.  308  et  sq. 


32  STUDIES  IN  ANIMAL   LIFE. 

question  here,  let  us  merely  note  that  the  Monosto- 
mum,  into  which  the  Cercaria  will  develop,  produces 
eggs,  from  which  young  will  issue ;  the  second  gen- 
eration is  not  produced  from  eggs,  but  by  internal 
budding;  the  third  generation  is  likewise  budded 
internally,  but  it,  on  acquiring  maturity,  will  pro- 
duce eggs.  For  this  maturity,  it  is  indispensable 
that  the  Cercaria  should  be  swallowed  by  some  bird 
or  animal ;  only  in  the  digestive  tube  can  it  acquire 
its  producing  condition.  How  is  it  to  get  there  ? 
The  ways  are  many ;  let  us  witness  one : 

In  this  watch-glass  of  water  we  have  several  Cer- 
carice  swimming  about.  To  them  we  add  three  or 
four  of  those  darting,  twittering  insects  which  you 
have  seen  in  every  vase  of  pond- water,  and  have 
learned  to  be  the  larvae  or  early  forms  of  the 
Ephemeron.  The  Cercaricz  cease  napping  the  water 
with  their  impatient  tails,  and  commence  a  severe 
scrutiny  of  the  strangers.  When  Odry,  in  the  riot- 
ous farce  Les  Saltimbanques,  finds  a  portmanteau,  he 
exclaims,  ".Un  mallei  ce  doit  etre  d  moil"  ("Surely 
this  must  belong  to  me!")  This  seems  to  be  the 
theory  of  property  adopted  by  the  Cercaria:  "An 
insect!  surely  this  belongs  to  me!"  Accordingly 
every  one  begins  creeping  over  the  bodies  of  the 
Ephemera,  giving  an  interrogatory  poke  with  the 
spine,  which  will  pierce  the  first  soft  place  it  can 
detect.  Between  the  segments  of  the  insect's  armor 
a  soft  and  pierceable  spot  is  found ;  and  now,  lads, 
to  work!  Onward  they  bore,  never  relaxing  in 


STUDIES  IN  ANIMAL  LIFE.  33 

their  efforts  till  a  hole  is  made  large  enough  for 
them  to  slip  in  by  elongating  their  bodies.  Once 
in,  they  dismiss  their  tails  as  useless  appendages, 
and  begin  what  is  called  the  process  of  encysting — 
that  is,  of  rolling  themselves  up  into  a  ball,  and  se- 
creting a  mucus  from  their  surface  which  hardens 
round  them  like  a  shell.  Thus  they  remain  snugly 
ensconced  in  the  body  of  the  insect,  which  in  time 
develops  into  a  fly,  hovers  over  the  pond,  and  is 
swallowed  by  some  bird.  The  fly  is  digested,  and 
the  liberated  Cercaria  finds  itself  in  comfortable 
quarters,  its  shell  is  broken,  and  its  progress  to  ma- 
turity is  rapid. 

Yon  Siebold's  description  of  another  form  of  em- 
igration he  has  observed  in  parasites  will  be  read 
with  interest.  "For  a  long  time,"  he  says,  "the 
origin  of  the  thread-worm,  known  as  Filaria  insec- 
torumj  that  lives  in  the  cavity  of  the  bodies  of  adult 
and  larval  insects,  could  not  be  accounted  for.  Shut 
up  within  the  abdominal  cavity  of  caterpillars,  grass- 
hoppers, beetles,  and  other  insects,  these  parasites 
were  supposed  to  originate  by  spontaneous  genera- 
tion under  the  influence  of  wet  weather  or  from  de- 
cayed food.  Helminthologists  (students  of  parasitic 
worms)  were  obliged  to  content  themselves  with 
this  explanation,  since  they  were  unable  to  find  a 
better.  Those  who  dissected  these  thread-worms, 
and  submitted  them  to  a  careful  inspection,  could 
not  deny  the  probability,  since  it  was  clear  that  they 
contained  no  trace  of  sexual  organs.  But,  on  di- 
B2 


34:  STUDIES  IN  ANIMAL  LIFE. 

recting  my  attention  to  these  entozoa,  I  became 
aware  of  the  fact  that  they  were  not  true  Filarice,  at 
all,  but  belonged  to  a  peculiar  family  of  thread- 
worms, embracing  the  genera  of  Gordius  and  Her- 
mis.  Furthermore,  I  convinced  myself  that  these 
parasites  wander  away  when  full  grown,  boring 
their  way  from  within  through  any  soft  place  in 
the  body  of  their  host,  and  creeping  out  through 
the  opening.  These  parasites  do  not  emigrate  be- 
cause they  are  uneasy,  or  because  the  caterpillar  is 
sickly,  but  from  that  same  internal  necessity  which 
constrains  the  horsefly  to  leave  the  stomach  of  the 
horse  where  he  has  been  reared,  or  which  moves 
the  gadfly  to  work  its  way  out  through  the  skin  of 
the  ox.  The  larvae  of  both  these  insects  creep  forth 
in  order  to  become  chrysalises,  and  thence  to  pro- 
ceed to  their  higher  and  perfect  condition.  I  have 
demonstrated  that  the  perfect,  full-grown,  but  sex- 
less thread- worms  of  insects  are  in  like  manner 
moved  by  their  desire  to  wander  out  of  their  pre- 
vious homes  in  order  to  enter  upon  a  new  period 
of  their  lives,  which  ends  in  the  development  of 
their  sex.  As  they  leave  the  bodies  of  their  hosts, 
they  fall  to  the  ground  and  crawl  away  into  the 
deeper  and  moister  parts  of  the  soil.  Thread- 
worms found  in  the  damp  earth,  in  digging  up  gar- 
dens and  cutting  ditches,  have  often  been  brought 
to  me  which  presented  no  external  distinctions  from 
the  thread- worms  of  insects.  This  suggested  to  me 
that  the  wandering  thread- worms  of  insects  might 


STUDIES  IN"  ANIMAL  LIFE.  35 

instinctively  bury  themselves  in  damp  ground,  and 
I  therefore  instituted  a  series  of  experiments  by 
placing  the  newly-emigrated  worms  in  flower-pots 
filled  with  damp  earth.  To  my  delight,  I  soon  per- 
ceived that  they  began  to  bore  with  their  heads  into 
the  earth,  and  by  degrees  drew  themselves  entirely 
in.  For  many  months  I  kept  the  earth  in  the  flow- 
er-pots moderately  moist,  and,  on  examining  the 
worms  from  time  to  time,  I  found  they  had  gradu- 
ally attained  their  sex-development,  and  eggs  were 
deposited  in  hundreds.  Toward  the  conclusion  of 
winter  I  could  succeed  in  detecting  the  commencing 
development  of  the  embryos  in  these  eggs.  By  the 
end  of  spring  they  were  fully  formed,  and  many  of 
them,  having  left  their  shells,  were  to  be  seen  creep- 
ing about  the  earth.  I  now  conjectured  that  these 
young  worms  would  be  impelled  by  their  instincts 
to  pursue  a  parasitic  existence,  and  to  seek  out  an 
animal  to  inhabit  and  to  grow  to  maturity  in ;  and 
it  seemed  not  improbable  that  the  brood  I  had 
reared  would,  like  their  parents,  thrive  best  in  the 
caterpillar.  In  order,  therefore,  to  induce  my  young 
brood  to  immigrate,  I  procured  a  number  of  very 
small  caterpillars,  which  the  first  spring  sunshine 
had  just  called  into  life.  For  the  purpose  of  my 
experiment,  I  filled  a  watch-glass  with  damp  earth, 
taking  it  from  among  the  flower-pots  where  the 
thread-worms  had  wintered.  Upon  this  I  placed 
several  of  the  young  caterpillars."  The  result  was 
as  he  expected;  the  caterpillars  were  soon  bored 


36  STUDIES  IN  ANIMAL  LIFE. 

into  by  the  worms,  and  served  them  at  once  as  food 
and  home.* 

Frogs  and  parasites,  worms  and  infusoria — are 
these  worth  the  attention  of  a  serious  man  ?  They 
have  a  less  imposing  appearance  than  planets  and 
asteroids  I  admit,  but  they  are  nearer  to  us,  and  ad- 
mit of  being  more  intimately  known,  and,  because 
they  are  thus  accessible,  they  become  more  import- 
ant to  us.  The  life  that  stirs  within  us  is  also  the 
life  within  them.  It  is  for  this  reason,  as  I  said  at 
the  outset,  that,  although  man's  noblest  study  must 
always  be  man,  there  are  other  studies  less  noble, 
yet  not  therefore  ignoble,  which  must  be  pursued, 
even  if  only  with  a  view  to  the  perfection  of  the 
noblest.  Many  men,  and  these  not  always  the  ig- 
norant, whose  scorn  of  what  they  do  not  under- 
stand is  always  ready,  despise  the  labors  which  do 
not  obviously  and  directly  tend  to  moral  or  political 
advancement.  Others  there  are  who,  fascinated  by 
the  grandeur  of  Astronomy  and  Geology,  or  by  the 
immediate  practical  results  of  Physics  and  Chem- 
istry, disregard  all  microscopic  research  as  little  bet- 
ter than  dilettante  curiosity.  But  I  can  not  think 
any  serious  study  is  without  its  serious  value  to  the 
human  race;  and  I  know  that  the  great  problem 
of  Life  can  never  be  solved  while  we  are  in  igno- 
rance of  its  simpler  forms.  Nor  can  any  thing  be 
more  unwise  than  the  attempt  to  limit  the  sphere 

*  VON  SIEBOLD  :   Ueber  Band-und-Blasenwurmer.     Translated 
by  HUXLEY. 


STUDIES  IN  ANIMAL  LIFE.  37 

of  human  inquiry,  especially  by  applying  the  test 
of  immediate  utility.  All  truths  are  related ;  and, 
however  remote  from  our  daily  needs  some  partic- 
ular truth  may  seem,  the  time  will  surely  come 
when  its  value  will  be  felt.  To  the  majority  of  our 
countrymen  during  the  Eevolution,  when  the  con- 
duct of  James  seemed  of  incalculable  importance, 
there  would  have  seemed  something  ludicrously  ab- 
surd in  the  assertion  that  the  newly-discovered  dif- 
ferential calculus  was  infinitely  more  important  to 
England  and  to  Europe  than  the  fate  of  all  the  dy- 
nasties; and  few  things  could  have  seemed  more 
remote  from  any  useful  end  than  this  product  of 
mathematical  genius ;  yet  it  is  now  clear  to  every 
one  that  the  conduct  of  James  was  supremely  insig- 
nificant in  comparison  with  this  discovery.  I  do 
not  say  that  men  were  unwise  to  throw  themselves 
body  and  soul  into  the  Eevolution ;  I  only  say  they 
would  have  been  unwise  to  condemn  the  researches 
of  mathematicians. 

Let  all  who  have  a  longing  to  study  Nature  in 
any  of  her  manifold  aspects  do  so  without  regard 
to  the  sneers  or  objections  of  men  whose  tastes  and 
faculties  are  directed  elsewhere.  From  the  illumi- 
nation of  many  minds  on  many  points  Truth  must 
finally  emerge.  Man  is,  in  Bacon's  noble  phrase, 
the  minister  and  interpreter  of  Nature ;  let  him  be 
careful  lest  he  suffer  this  ministry  to  sink  into  a 
priesthood,  and  this  interpretation  to  degenerate 
into  an  immovable  dogma.  The  suggestions  of 


38  STUDIES  IN  ANIMAL  LIFE. 

apathy  and  the  prejudices  of  ignorance  have  at  all 
times  inspired  the  wish  to  close  the  temple  against 
new  comers.  Let  us  be  vigilant  against  such  sug- 
gestions, and  keep  the  door  of  the  temple  ever 
open. 


STUDIES   IN  ANIMAL   LIFE.  39 


CHAPTER  H. 

Ponds  and  Rock-pools. — Oar  necessary  Tackle. — Wimbledon 
Common.  —  Early  Memories. —  Gnat  Larvae. — Entomostraca 
and  their  Paradoxes. — Races  of  Animals  dispensing  with  the 
sterner  Sex. — Insignificance  of  Males. — Volvox  Globator :  is  it 
an  Animal  ? — Plants  swimming  like  Animals. — Animal  Retro- 
gressions.— The  Dytiscus  and  its  Larva. — The  Dragon-fly  Lar- 
va.— Mollusks  and  their  Eggs. — Polypes,  and  how  to  find  them. 
— A  new  Polype,  Hydra  rubra. — Nest-building  Fish. — Con- 
tempt replaced  by  Reverence. 

THE  day  is  bright  with  a  late  autumn  sun ;  the 
sky  is  clear  with  a  keen  autumn  wind,  which  lashes 
our  blood  into  a  canter  as  we  press  against  it,  and 
the  cantering  blood  sets  the  thoughts  into  hurrying 
excitement.  Wimbledon  Common  is  not  far  off; 
its  five  thousand  acres  of  undulating  heather,  furze, 
and  fern  tempt  us  across  it,  health  streaming  in  at 
every  step  as  we  snuff  the  keen  breeze.  "We  are 
tempted  also  to  bring  net  and  wide-mouthed  jar,  to 
ransack  its  many  ponds  for  visible  and  invisible 
wonders. 

Ponds,  indeed,  are  not  so  rich  and  lovely  as  rock- 
pools  ;  the  heath  is  less  alluring  than  the  coast — 
our  dear-loved  coast,  with  its  gleaming  mystery,  the 
sea,  and  its  sweeps  of  sand,  its  reefs,  its  dripping 
boulders.  I  admit  the  comparative  inferiority  of 
ponds,  but,  you  see,  we  are  not  near  the  coast,  and 


40  STUDIES  IN  ANIMAL   LIFE. 

the  heath  is  close  at  hand.  Nay,  if  the  case  were 
otherwise,  I  should  object  to  dwarfing  comparisons. 
It  argues  a  pitiful  thinness  of  nature  (and  the  major- 
ity in  this  respect  are  lean)  when  present  excellence 
is  depreciated  because  some  greater  excellence  is  to 
be  found  elsewhere.  We  are  not  elsewhere;  we 
must  do  the  best  we  can  with  what  is  here.  Be- 
cause ours  is  not  the  Elizabethan  age,  shall  we  ex- 
press no  reverence  for  our  great  men,  but  reserve 
it  for  Shakspeare,  Bacon,  and  Ealeigh,  whose  tra- 
ditional renown  must  overshadow  our  contempo- 
raries? Not  so.  To  each  age  its  honor.  Let  us 
be  thankful  for  all  greatness,  past  or  present,  and 
never  speak  slightingly  of  noble  work  or  honest 
endeavor  because  it  is  not,  or  we  choose  to  say  it  is 
not,  equal  to  something  else.  No  comparisons,  then, 
I  beg.  If  I  said  ponds  were  finer  than  rock-pools, 
you  might  demur ;  but  I  only  say  ponds  are  excel- 
lent things,  let  us  dabble  in  them;  ponds  are  rich 
in  wonders,  let  us  enjoy  them. 

And,  first,  we  must  look  to  our  tackle.  It  is  ex- 
tremely simple.  A  landing-net,  lined  with  muslin ; 
a  wide-mouthed  glass  jar,  say  a  foot  high  and  six 
inches  in  diameter,  but  the  size  optional,  with  a  bit 
of  string  tied  under  the  lip,  and  forming  a  loop  over 
the  top,  to  serve  as  a  handle,  which  will  let  the  jar 
swing  without  spilling  the  water ;  a  camel's-hair 
brush ;  a  quinine  bottle,  or  any  wide-mouthed  phi- 
al, for  worms  and  tiny  animals  which  you  desire  to 
keep  separated  from  the  dangers  and  confusions  of 


STUDIES  IN  ANIMAL  LIFE.  41 

the  larger  jar;  and  when  to  these  a  pocket  lens  is 
added,  our  equipment  is  complete. 

As  we  emerge  upon  the  common  and  tread  its 
springy  heather,  what  a  wild  wind  dashes  the  hair 
into  our  eyes,  and  the  blood  into  our  cheeks !  and 
what  a  fine  sweep  of  horizon  lies  before  us !  The 
lingering  splendors  and  the  beautiful  decays  of  au- 
tumn vary  the  scene,  and  touch  it  with  a  certain 
pensive  charm.  The  ferns  mingle  harmoniously 
their  rich  browns  with  the  dark  green  of  the  furze, 
now  robbed  of  its  golden  summer  glory,  but  still 
pleasant  to  the  eye  and  exquisite  to  memory.  The 
gaunt  wind-mill  on  the  rising  ground  is  stretching 
its  stiff,  starred  arms  into  the  silent  air,  a  land- 
mark for  the  wanderer — a  land-mark,  too,  for  the 
wandering  mind,  since  it  serves  to  recall  the  dim 
early  feelings  and  sweet  broken  associations  of  a 
childhood  when  we  gazed  at  it  with  awe,  and  listen- 
ed to  the  rushing  of  its  mighty  arms.  Ah !  well 
may  the  mind  with  the  sweet  insistance  of  sadness 
linger  on  those  scenes  of  the  irrecoverable  past,  and 
try,  by  lingering  there,  to  feel  that  it  is  not  wholly 
lost,  wholly  irrecoverable,  vanished  forever  from  the 
Life  which,  as  these  decays  of  autumn  and  these 
changing  trees  too  feelingly  remind  us,  is  gliding 
away,  leaving  our  cherished  ambitions  still  unful- 
filled, and  our  deeper  affections  still  but  half  ex-, 
pressed.  The  vanishing  visions  of  elapsing  life 
bring  with  them  thoughts  which  lie  too  deep  for 
tears,  and  this  wind-mill  recalls  such  visions  by 


42  STUDIES  IN  ANIMAL  LIFE. 

the  subtle  laws  of  association.  Let  us  go  toward  it, 
and  stand  once  more  under  its  shadow.  See  the  in- 
telligent and  tailless  sheep-dog  which  bounds  out  at 
our  approach,  eager  and  minatory ;  now  his  quick 
eye  at  once  recognizes  that  we  are  neither  tramps 
nor  thieves,  and  he  ceases  barking  to  commence  a 
lively  interchange  of  sniffs  and  amenities  with  our 
Pug,  who  seems  also  glad  of  a  passing  interchange 
of  commonplace  remarks.  While  these  dogs  travel 
over  each  other's  minds,  let  us  sun  ourselves  upon 
this  bench,  and  look  down  on  the  embrowned  val- 
ley, with  its  gipsy  encampment,  or  abroad  on  the 
purple  Surrey  hills,  or  the  varied-tinted  trees  of 
Combe  Wood  and  Richmond  Park.  There  are  not 
many  such  prospects  so  near  London.  But,  in 
spite  of  the  sun,  we  must  not  linger  here :  the  wind 
is  much  too  analytical  in  its  remarks ;  and,  more- 
over, we  came  out  to  hunt. 

Here  is  a  pond  with  a  mantling  surface  of  green 
promise.  Dip  the  jar  into  the  water.  Hold  it  now 
up  to  the  light,  and  you  will  see  an  immense  varie- 
ty of  tiny  animals  swimming  about.  Some  are 
large  enough  to  be  recognized  at  once;  others  re- 
quire a  pocket  lens,  unless  familiarity  has  already 
enabled  you  to  infer  the  forms  you  can  not  distinct- 
ly see.  Here  (Fig.  7)  are  two  larvae  (or  grubs)  of 
the  common  gnat.  That  large-headed  fellow  (A) 
bobbing  about  with  such  grotesque  movements  is 
very  near  the  last  stage  of  his  metamorphosis, 
and  to-morrow,  or  the  next  day,  you  may  see  him 


STUDIES  IN  ANIMAL  LIFE. 


Fig.  7. — LABV./E  OP  THE  GNAT  in  two  different  stages  of  development 
(magnified). 

cast  aside  this  mask  (larva  means  a  mask),  and 
emerge  a  perfect  insect.  The  other  (B)  is  in  a 
much  less  matured  condition,  but  leads  an  active 
predatory  life,  jerking  through  the  water,  and  fast- 
ening to  the  stems  of  weed  or  sides  of  the  jar  by 
means  of  the  tiny  hooks  at  the  end  of  its  tail.  The 
hairy  appendage  forming  the  angle  is  not  another 
tail,  but  a  breathing  apparatus. 

Observe,  also,  those  grotesque  Entomostraca* 
popularly  called  "water-fleas,"  although,  as  you 
perceive,  they  have  little  resemblance  in  form  or 
manners  to  our  familiar  (somewhat  too  familiar) 
bed-fellows.  This  (Fig.  8)  is  a  Cyclops,  with  only 
one  eye  in  the  centre  of  its  forehead,  and  carrying 
two  sacs,  filled  with  eggs,  like  panniers.  You  ob- 

*  Entomostraca  (from  entomos,  an  insect,  and  ostracon,  a  shell) 
are  not  really  insects,  but  belong  to  the  same  large  group  of  ani- 
mals as  the  lobster,  the  crab,  or  the  shrimp — i.  e.,  crustaceans. 


44 


STUDIES  IN  ANIMAL  LIFE. 


serve  he  has  no  legs ;  or, 
rather,  legs  and  arms  are 


Fig.  8 CYCLOPS. 

a,  large  antennae ;  6,  smaller  do. ; 
c,  egg-sacs  (magnified). 


Fig.  9.— DAPHNIA. 

a,  pulsatile  sac,  or  heart ;  6,  eggs ; 
c,  digestive  tube  (magnified). 


hoisted  up  to  the  head,  and  become  antennae  (or 
feelers).  Here  (Fig.  9)  is  a  Daphnia,  grotesque 
enough,  throwing  up  his  arms  in  astonished  awk- 
wardness, and  keeping 
his  legs  actively  at  work 
inside  the  shell — as  res- 
pirators, in  fact.  Here 
(Fig.  10)  is  a  Eurycer- 
cus,  less  grotesque,  and 
with  a  much  smaller  eye. 
Talking  of  eyes,  there  is 


Fig.  10.— EUEYCEKCUS. 
a,  heart ;  &,  eggs ;  c,  digestiv< 
(magnified). 


tube 


one  of  these  Entomos- 
traca,  named  Polyphemus,  whose  head  is  all  eye; 
and  another,  named  Caligus,  who  has  no  head  at  all. 
Other  paradoxes  and  wonders  are  presented  by  this 
interesting  group  of  animals  ;*  but  they  all  sink 

*  The  student  will  find  ample  information  in  BAIRD'S  British 
Entomostraca,  published  by  the  Kay  Society. 


STUDIES  IN  ANIMAL   LIFE.  45 

into  insignificance  beside  the  paradox  of  the  ama- 
zonian  entomostracon,  the  Apus — a  race  which  dis- 
penses with  masculine  services  altogether,  a  race  of 
which  there  are  no  males ! 

I  well  remember  the  pleasant  evening  on  which 
I  first  made  the  personal  acquaintance  of  this  ama- 
zon.  It  was  at  Munich,  and  in  the  house  of  a  cele- 
brated naturalist,  in  whose  garden  an  agreeable  as- 
semblage of  poets,  professors,  and  their  wives  saun- 
tered in  the  light  of  a  setting  sun,  breaking  up  into 
groups  and  tetes-d-tetes,  to  re-form  into  larger  groups. 
We  had  taken  coffee  under  the  branching  coolness 
of  trees,  and  were  now  loitering  through  the  brief 
interval  till  supper.  Our  host  had  just  returned 
from  an  expedition  of  some  fifty  miles  to  a  particu- 
lar pond,  known  to  be  inhabited  by  the  Apus.  He 
had  made  this  journey  because  the  race,  although 
prolific,  is  rare,  and  is  not  to  be  found  in  every  spot. 
For  three  successsive  years  had  he  gone  to  the  same 
pond  in  quest  of  the  male ;  but  no  male  was  to  be 
found  among  thousands  of  egg-bearing  females, 
some  of  which  he  had  brought  away  with  him,  and 
was  showing  us.  We  were  amused  to  see  them 
swimming  about,  sometimes  on  their  backs,  using 
their  long  oars,  sometimes  floating,  but  always  in- 
cessantly agitating  the  water  with  their  ten  pairs 
of  breathing  legs ;  and  the  ladies,  gathered  round 
the  jar,  were  hugely  elated  at  the  idea  of  animals 
getting  rid  altogether  of  the  sterner  sex — clearly  a 
useless  encumbrance  in  the  scheme  of  things ! 


46  STUDIES  IN  ANIMAL   LIFE. 

The  fact  that  no  male  Apus  has  yet  been  found 
is  not  without  precedent.  Leon  Dufour,  the  cele- 
brated entomologist,  declares  that  he  never  found 
the  male  of  the  gall  insect  (Diplolepis  gallce  tinctorice), 
though  he  has  examined  thousands :  they  were  all* 
females,  and  bore  well-developed  eggs  on  emerging 
from  the  gall-nut  in  which  their  infancy  had  pass- 
ed. In  two  other  species  of  gall  insect — Cynips  di- 
visa  and  Cynips  folii — Hartig  says  he  was  unable  to 
find  a  male ;  and  he  examined  about  thirteen  thou- 
sand. Brongniart  never  found  the  male  of  another 
entomostracon  (Limnadia  gigas),  nor  could  Jurine 
find  that  of  our  Polyphemus.  These  negatives 
prove,  at  least,  that  if  the  males  exist  at  all,  they 
must  be  excessively  rare,  and  their  services  can  be 
dispensed  with ;  a  conclusion  which  becomes  accept- 
able when  we  learn  that  bees,  plant-lice  (Aphides), 
and  our  grotesque  friend  Daphnia  (Fig.  9)  lay  eggs 
which  may  be  reared  apart,  will  develop  into  fe- 
males, and  these  will  produce  eggs  which  will  in 
turn  produce  other  females,  and  so  on,  generation 
after  generation,  although  each  animal  be  reared  in 
a  vessel  apart  from  all  others. 

While  on  this  subject,  I  can  not  forbear  making 
a  reflection.  It  must  be  confessed  that  our  sex  cuts 
but  a  poor  figure  in  some  great  families.  If  the 
male  is  in  some  families  grander,  fiercer,  more  splen- 
did, and  more  highly  endowed  than  the  female,  this 
occasional  superiority  is  more  than  counterbalanced 
by  the  still  greater  inferiority  of  the  sex  in  other 


OF  THE 
STUDIES  IN  ANIMAL  L«fIT  Jjf  J  "^  H51  5 

families.  The  male  is  often  but  a  contemptible 
partner,  puny  in  size,  insignificant  in  powers,  stint- 
ed even  of  a  due  allowance  of  organs.  If  the  pea- 
cock and  the  pheasant  swagger  in  greater  splendor, 
what  a  pitiful  creature  is  the  male  falcon  I — no  fal- 
coner will  look  at  him.  And  what  is  the  drone 
compared  with  the  queen  bee,  or  even  with  the 
workers  ?  What  figure  does  the  male  spider  make 
beside  his  large  and  irascible  female,  who  not  un- 
frequently  eats  him  ?  Nay,  worse  than  this,  what 
can  be  said  for  the  male  Eotifer,  the  male  Barnacle, 
the  male  Lernaea — gentlemen  who  can  not  even 
boast  of  a  perfect  digestive  apparatus,  sometimes 
not  of  a  digestive  organ  at  all  ?  Nor  is  this  mea- 
greness  confined  to  the  digestive  system  only.  In 
some  cases,  as  in  some  male  Kotifers,  the  usual  or- 
gans of  sense  and  locomotion  are  wanting  ;*  and  in 
a  parasitic  Lernaea,  the  degradation  is  moral  as  well 
as  physical :  the  female  lives  in  the  gills  of  a  fish, 
sucking  its  juices,  and  the  ignoble  husband  lives  as 
a  parasite  upon  her ! 

But  this  digression  is  becoming  humiliating,  and 
meanwhile  our  hands  are  getting  benumbed  with 
cold.  In  spite  of  that,  I  hold  the  jar  up  to  the 
light,  and  make  a  background  of  my  forefingers,  to 
throw  into  relief  some  of  the  transparent  animals. 
Look  at  those  green  crystal  spheres  sailing  along 

v  *  Compare  GEGENBAUR:  Gnmdzuge  der  vergldchende  Anato- 
rnie,  1859,  p.  229  und  269 ;  also  LEYDIG  iiber  Hydatina  senta,  in 
Miller's  Arckiv,  1857,  p.  411. 


48  STUDIES  IN   ANIMAL   LIFE. 


Fig.  11.—  VOLVOX  GLOBATOR,  with  eight  volvoces 
inclosed  (magnified). 

with  slow  revolving  motion,  like  planets  revolving 
through,  space,  except  that  their  orbits  are  more  ec- 
centric. Each  of  these  spheres  is  a  Volvox  globator. 
Under  the  microscope  it  looks  like  a  crystalline 
sphere,  studded  with  bright  green  specks,  from  each 
of  which  arise  two  cilia  (hairs),  serving  as  oars  to 
row  the  animal  through  the  water.  The  specks  are 
united  by  a  delicate  net-work,  which  is  not  always 
visible,  however.  Inside  this  sphere  is  a  fluid,  in 
which  several  dark  green  smaller  spheres  are  seen 
revolving,  as  the  parent  sphere  revolved  in  the  wa- 
ter. Press  this  Yolvox  gently  under  your  com- 
pressorium,  or  between  the  two  pieces  of  glass,  and 
you  will  see  these  internal  spheres,  when  duly  mag- 
nified, disclose  themselves  as  identical  with  their 
parent ;  and  inside  them  smaller  Volvoces  are 
seen.  This  is  one  of  the  many  illustrations  of  life 
within  life,  of  which  something  was  said  in  the  last 
chapter. 


STUDIES  IN  ANIMAL   LIFE.  49 

Nor  is  this  all.  Those  bright  green  specks  which 
stud  the  surface,  if  examined  with  high  powers,  will 
turn  out  to  be,  not  specks,  but  animals,*  and,  as  Eh- 
renberg  believes  (though  the  belief  is  but  little 
shared),  highly  organized  animals,  possessing  a 
mouth,  many  stomachs,  and  an  eye.  It  is  right  to 
add  that  not  only  are  microscopists  at  variance  with 
Ehrenberg  on  the  supposed  organization  of  these 
specks,  but  the  majority  deny  that  the  Yolvox  itself 
is  an  animal.  Yon  Siebold  in  Germany,  and  Pro- 
fessor George  Busk  and  Professor  Williamson  in 
England,  have  argued  with  so  much  force  against 
the  animal  nature  of  the  Yolvox,  which  they  call  a 
plant,  that  in  most  modern  works  you  will  find  this 
opinion  adopted.  But  the  latest  of  the  eminent  au- 
thorities on  the  subject  of  Infusoria,  in  his  magnifi- 
cent work  just  published,  returns  to  the  old  idea 
that  the  Yolvox  is  an  animal  after  all,  although  of 
very  simple  organization.f 

The  dispute  may  perhaps  excite  your  surprise. 
You  are  perplexed  at  the  idea  of  a  plant  (if  plant  it 
be)  moving  about,  swimming  with  all  the  vigor  and 
dexterity  of  an  animal,  and  swimming  by  means  of 
animal  organs,  the  cilia.  But  this  difficulty  is  one 
of  our  own  creation.  We  first  employ  the  word 

*  To  avoid  the  equiyoque  of  calling  the  parts  of  an  animal, 
\vhich  are  capable  of  independent  existence,  by  the  same  term  as 
the  whole  mass,  we  may  adopt  HUXLEY'S  suggestion,  and  call  all 
such  individual  parts  zooids  instead  of  animals.  DUGES  suggested 
zoonites  in  the  same  sense. — Sur  la  Conformite  Organique,  p.  13. 

i  STEIN  :  Der  Organismus  der  Infusionsthiere,  1859,  p.  36-38. 

c 


50  STUDIES  IN   ANIMAL   LIFE. 

plant  to  designate  a  vast  group  of  objects  which 
have  no  powers  of  locomotion,  and  then  ask,  with 
triumph,  How  can  a  plant  move?  But  we  have 
only  to  enlarge  our  knowledge  of  plant-life  to  see 
that  locomotion  is  not  absolutely  excluded  from  it; 
for  many  of  the  simpler  plants— Confervse  and  Al- 
gae— can  and  do  move  spontaneously  in  the  early 
stages  of  their  existence :  they  escape  from  their 
parents  as  free  swimming  rovers,  and  do  not  settle 
into  solid  and  sober  respectability  till  later  in  life. 
In  their  roving  condition  they  are  called,  improper- 
ly enough,  "  zoospores,"*  and  once  gave  rise  to  the 
opinion  that  they  were  animals  in  infancy,  and  be- 
came degraded  into  plants  as  their  growth  went  on. 
But  locomotion  is  no  true  mark  of  animal-nature, 
neither  is  fixture  to  one  spot  the  true  mark  of  plant- 
nature.  Many  animals  (Polypes,  Polyzoa,  Barna- 
cles, Mussels,  etc.),  after  passing  a  vagabond  youth, 
"  settle"  once  and  forever  in  maturer  age,  and  then 
become  as  fixed  as  plants.  Nay,  human  animals 
not  unfrequently  exhibit  a  somewhat  similar  me- 
tempsychosis, and  make  up  for  the  fitful  capricious- 
ness  of  wandering  youth  by  the  steady  severity  of 
their  application  to  business  when  width  of  waist- 
coat and  smoothness  of  cranium  suggest  a  sense  of 
their  responsibilities. 

Whether  this  loss  of  locomotion  is  to  be  regard- 
ed as  a  retrogression  on  the  part  of  the  plant  or 
animal  which  becomes  fixed,  may  be  questioned; 

*  Zoospores,  from  zoon,  an  animal,  and  s/>oros,  a  seed. 


STUDIES   IN  ANIMAL   LIFE.  51 

but  there  are  curious  indications  of  positive  retro- 
gression from  a  higher  standard  in  the  metamor- 
phoses of  some  animals.  Thus  the  beautiful  marine 
worm  Terebella,  which  secretes  a  tube  for  itself,  and 
lives  in  it,  fixed  to  the  rock  or  oyster-shell,  has  in 
early  life  a  distinct  head,  eyes,  and  feelers ;  but  in 
growing  to  maturity  it  loses  all  trace  of  head,  eyes, 
and  even  of  feelers,  unless  the  beautiful  tuft  of 
streaming  threads  which  it  waves  in  the  water  be 
considered  as  replacing  the  feelers.  There  are  the 
Barnacles,  too,  which  in  the  first  stage  of  their  ex- 
istence have  three  pairs  of  legs,  a  very  simple  single 
eye,  and  a  mouth  furnished  with  a  proboscis.  In 
the  second  stage  they  have  six  pairs  of  legs,  two 
compound  eyes  complex  in  structure,  two  feelers, 
but  no  mouth.  In  the  third,  or  final  stage,  their 
legs  are  transformed  into  prehensile  organs,  they 
have  recovered  a  mouth,  but  have  lost  their  feelers, 
and  their  two  complex  eyes  are  degraded  to  a  single 
and  very  simple  eye-spot. 

But,  to  break  up  these  digressions,  let  us  try  a 
sweep  with  our  net.  We  skim  it  along  the  surface, 
and  draw  up  a  quantity  of  duckweed,  dead  leaves, 
bits  of  stick,  and  masses  of  green  thread  of  great 
fineness,  called  Conferva  by  botanists.  The  water 
runs  away,  and  we  turn  over  the  mass.  Here  is  a 
fine  water-beetle,  called  the  "  Water-tiger,"  from  its 
ferocity  (Fig.  12).  You  would  hardly  suspect  that 
the  slim,  big-headed,  long-tailed  Water-tiger  would 
grow  into  the  squat,  small-headed,  tailless  beetle ; 


52 


STUDIES   IN   ANIMAL   LIFE. 


Fig.  12.— WATEE  BEETLE  and  its  larva. 

nor  would  you  imagine  that  this  Water-tiger  would 

be  so  "high  fantas- 
tical" as  to  breathe 
by  his  tail.  Yet  he 
does  both,  as  you  will 
find  if  you  watch 
him  in  your  aqua- 
rium. 

Continuing  our 
search,  we  light  up- 
on the  fat,  sluggish, 
ungraceful  larva  of 
the  graceful  and  bril- 
liant Dragon-fly,  the 
falcon  of  insects  (Fig. 
13).  He  is  useful 
for  dissection,  so  pop 
Fig.i3.-DBAGON-FLYLARv,E:  him  in.  Among  the 

A,  ordinary  aspect;  B,  with  the  huge  nipper- 

like  jaw  extended.  dead  leaves  you  per- 


STUDIES   IN   ANIMAL   LIFE. 


53 


ceive  several  small  leeches,  and  flat  oval  Plana- 
rice,  white  and  brown ;  and  here  also  is  a  jelly- 
like  mass,  of  pale  yellow  color,  which  we  know 
to  be  a  mass  of  eggs  deposited  by  some  shell- 
fish; and,  as  there  are  few  objects  of  greater  inter- 
est than  an  egg  in  course  of  development,  we  pop 
the  mass  in.  Here  (Fig.  14)  are  two  mollusks,  Lim- 


Fig.  14— A,  LIMN^US  STAGNALIS,  or  Water-snail. 


B,  PLANOBBIS. 


nceus  and  Planorbis,  one  of  which  is  probably  the 
parent  of  those  eggs. 
And  here  is  one  which 
lays  no  eggs,  but  brings 
forth  its  young  alive :  it 
is  the  Paludina  vivipara 
(Fig.  15),  of  which  we 
learned  some  interest- 
ing details  last  month.  Fig.  IS.— PALCDIHA  VIVH-AKA. 


54  STUDIES  IN   ANIMAL   LIFE. 

Scattered  over  the  surface  of  the  net  and  dead  leaves 
are  little  dabs  of  dirty -looking  jelly — some  of  them, 
instead  of  the  dirty  hue,  are  almost  blood-red.  Ex- 
perience makes  me  aware  that  these  dirty  dabs  are 
certainly  Polypes — the  Hydra  fusca  of  systematists. 
I  can't  tell  how  it  is  I  know  them,  nor  how  you  may 
know  them  again.  The  power  of  recognition  must 
be  acquired  by  familiarity ;  and  it  is  because  men 
can't  begin  with  familiarity,  and  can't  recognize  these 
Polypes  without  it,  that  so  few  persons  really  ever 
see  them.  But  the  familiarity  may  be  acquired  by  a 
very  simple  method.  Make  it  a  rule  to  pop  every 
unknown  object  into  your  wide-mouthed  phial.  In 
the  water  it  will  probably  at  once  reveal  its  nature : 
if  it  be  a  Polype,  it  will  expand  its  tentacles ;  if  not, 
you  can  identify  it  at  leisure  on  reaching  home  by 
the  aid  of  pictures  and  descriptions.  See,  as  I  drop 
one  of  these  into  the  water,  it  at  once  assumes  the  well- 
known  shape  of  the  Polype.  And  now  we  will  see 
what  these  blood-red  dabs  may  be ;  in  spite  of  their 
unusual  color,  I  can  not  help  suspecting  them  to  be 
Polypes  also.  Give  me  the  camel-hair  brush.  Gen- 
tly the  dab  is  removed,  and  transferred  to  the  phial. 
Shade  of  Trembley !  it  is  a  Polype  !*  Is  it  possible 
that  this  discovery  leaves  you  imperturbable,  even 

*  TREMBLEY,  in  his  admirable  work,  Memoires  pour  servir  a 
Vkistoire  dune  genre  de  Polypes  deau  dome,  1744,  furnished  science 
with  the  fullest  and  most  accurate  account  of  fresh-water  Polypes ; 
but  it  is  a  mistake  to  suppose  that  he  was  the  original  discoverer  of 
this  genus :  old  LEUWENHOEK  had  been  before  him. 


STUDIES   IN   ANIMAL   LIFE.  55 

when  I  assure  you  it  is  of  a  species  hitherto  unde- 
scribed  in  text-books  ?  Now  don't  be  provokingly 
indifferent !  rouse  yourself  to  a  little  enthusiasm, 
and  prove  that  you  have  something  of  the  natural- 
ist in  you  by  delighting  in  the  detection  of  a  new 
species.  "You  didn't  know  that  it  was  new?" 
That  explains  your  calmness.  There  must  be  a 
basis  of  knowledge  before  wonder  can  be  felt — 
wonder  being,  as  Bacon  says,  "  broken  knowledge." 
Learn,  then,  that  hitherto  only  three  species  of 
fresh-water  Polypes  have  been  described:  Hydra 
viridis,  Hydra  fusca,  and  Hydra  grisea.  We  have 
now  a  fourth  to  swell  the  list;  we  will  christen  it 
Hydra  rubra,  and  be  as  modest  in  our  glory  as  we 
can.  If  any  one  puts  it  to  us  whether  we  seriously 
attach  importance,  to  such  trivialities  as  specific  dis- 
tinctions resting  solely  upon  color  or  size,  we  can 
look  profound,  you  know,  and  repudiate  the  charge. 
But  this  is  a  public  and  official  attitude.  In  pri- 
vate we  can  despise  the  distinctions  established  by 
others,  but  keep  a  corner  of  favoritism  for  our  own.* 
I  remember  once  showing  a  bottle  containing 
Polypes  to  a  philosopher,  who  beheld  them  with 
great  calmness.  They  appeared  to  him  as  insignifi- 

*  The  editors  of  the  Annals  of  Natural  History  append  a  note  to 
the  account  I  sent  them  of  this  new  Polype,  from  which  it  appears 
that  Dr.  Gray  found  this  very  species,  and  apparently  in  the.  same 
spot,  nearly  thirty  years  ago.  But  the  latest  work  of  authority, 
VAN  DER  HOVEN'S  Handbook  of  Zoology,  only  enumerates  the  three 
species. 


56  STUDIES   IN   ANIMAL    LIFE. 

cant  as  so  many  stems  of  duckweed  ;  and,  lest  you 
should  be  equally  indifferent,  I  will  at  once  inform 
you  that  these  creatures  will  interest  you  as  much 
as  any  that  can  be  found  in  ponds,  if  you  take  the 
trouble  of  studying  them.  They  can  be  cut  into 
many  pieces,  and  each  piece  will  grow  into  a  per- 
fect Polype ;  they  may  be  pricked  or  irritated,  and 
the  irritated  spot  will  bud  a  young  Polype,  as  a 
plant  buds;  they  may  be  turned  inside  out,  and 
their  skin  will  become  a  stomach,  their  stomach  a 
skin.  They  have  acute  sensibility  to  light  (toward 
which  they  always  move),  and  to  the  slightest  touch; 
yet  not  a  trace  of  a  nervous  tissue  is  to  be  found  in 
them.  They  have  powers  of  motion  and  locomo- 
tion, yet  their  muscles  are  simply  a  network  of 
large  contractile  cells.  If  the  water  in  which  they 
are  kept  be  not  very  pure,  they  will  be  found  in- 
fested with  parasites ;  and  quite  recently  I  have  no- 
ticed an  animal  or  vegetal  parasite — I  know  not 
which — forming  an  elegant  sort  of  fringe  to  the 
tentacles ;  clusters  of  skittle-shaped  bodies,  too  en- 
tirely transparent  for  any  structure  whatever  to  tie 
made  out,  in  active  agitation,  like  leaves  fluttering 
on  a  twig.  Some  day  or  other  we  may  have  occa- 
sion to  treat  of  the  Polypes  in  detail,  and  to  narrate 
the  amusing  story  of  their  discovery ;  but  what  has 
already  been  said  will  serve  to  sharpen  your  atten- 
tion, and  awaken  some  curiosity  in  them. 

Again  and  again  the  net  sweeps  among  the  weed 
or  dredges  the  bottom  of  the  pond,  bringing  up  mud, 


STUDIES   IN   ANIMAL   LIFE.  57 

stones,  sticks,  with  a  fish,  worms,  mollusks,  and  tri- 
tons.  The  fish  we  must  secure,  for  it  is  a  stickle- 
back— a  pretty  and  interesting  inhabitant  of  an 
aquarium,  on  account  of  its  nest-building  propensi- 
ties. We  are  surprised  at  a  fish  building  a  nest 
and  caring  for  its  young  like  the  tenderest  of  birds 
(and  there  are  two  other  fishes,  the  Goramy  and  the 
Hassar,  which  have  this  instinct);  but  why  not  a 
fish  as  well  as  a  bird?  The  catfish  swims  about 
in  company  with  her  young,  like  a  proud  hen  with 
her  chickens,  and  the  sunfish  hovers  for  weeks  over 
her  eggs,  protecting  them  against  danger. 

The  wind  is  so  piercing,  and  my  fingers  are  so 
benumbed,  I  can  scarcely  hold  the  brush.  More- 
over, continual  stooping  over  the  net  makes  the 
muscles  ache  unpleasantly,  and  suggests  that  each 
cast  shall  be  the  final  one.  But  somehow  I  have 
made  this  resolution  and  broken  it  twenty  times : 
either  the  cast  has  been  unsuccessful,  and  one  is 
provoked  to  try  again,  or  it  is  so  successful  that,  as 
Tappetit  vient  en  mangeant,  one  is  seduced  again. 
Yery  unintelligible  this  would  be  to  the  passers- 
by,  who  generally  cast  contemptuous  glances  at  us 
when  they  find  we  are  not  fishing,  but  are  only  re- 
moving nothings  into  a  glass  jar.  One  day  an 
Irish  laborer  stopped  and  asked  me  if  I  were  fish- 
ing for  salmon.  I  quietly  answered  "Yes."  He 
drew  near.  I  continued  turning  over  the  weed,  oc- 
casionally dropping  an  invisible  thing  into  the  wa- 
ter. At  last  a  large  yellow-bellied  Triton  was 
C2 


58  STUDIES  IN    ANIMAL   LIFE. 

dropped  in.  He  begged  to  see  it;  and,  seeing  at 
the  same  time  how  alive  the  water  was  with  tiny 
animals,  became  curious,  and  asked  many  questions. 
I  went  on  with  my  work ;  his  interest  and  curiosity 
increased ;  his  questions  multiplied ;  he  volunteered 
assistance ;  and  remained  beside  me  till  I  prepared 
to  go  away,  when  he  said  seriously,  "Och!  then, 
and  it's  a  fine  thing  to  be  able  to  name  all  God's 
creatures."  Contempt  had  given  place  to  rever- 
ence ;  and  so  it  would  be  with  others,  could  they 
check  the  first  rising  of  scorn  at  what  they  do  not 
understand,  and  patiently  learn  what  even  a  road- 
side pond  has  of  Nature's  wonders. 


STUDIES   IN   ANIMAL   LIFE.  69 


CHAPTER  HI. 

A  garden  Wall,  and  its  Traces  of  past  Life. — Not  a  Breath  per- 
ishes.—A  Bit  of  dry  Moss  and  its  Inhabitants.— The  "Wheel- 
bearers." —  Resuscitation  of  Rotifers:  drowned  into  Life. — 
Current  Belief  that  Animals  can  be  revived  after  complete  De- 
siccation.— Experiments  contradicting  the  Belief. — Spallanzani's 
Testimony. — Value  of  Biology  as  a  Means  of  Culture. — Classi- 
fication of  Animals :  the  five  great  Types. — Criticism  of  Cu- 
vier's  Arrangement. 

PLEASANT,  both  to  eye  and  mind,  is  an  old  gar- 
den wall,  dark  with  age,  gray  with  lichens,  green 
with  mosses*  of  beautiful  hues  and  fairy  elegance  of 
form ;  a  wall  shutting  in  some  sequestered  home, 
far  from  "the  din  of  murmurous  cities  vast;"  a 
home  where,  as  we  fondly,  foolishly  think,  Life 
must  needs  throb  placidly,. and  all  its  tragedies  and 
pettinesses  be  unknown.  As  we  pass  alongside  this 
wall,  the  sight  of  the  overhanging  branches  sug- 
gests an  image  of  some  charming  nook;  or  our 
thoughts  wander  about  the  wall  itself,  calling  up 
the  years  during  which  it  has  been  warmed  by  the 
sun,  chilled  by  the  night  airs  and  the  dews,  and 
dashed  against  by  the  wild  winds  of  March,  all  of 
which  have  made  it  quite  another  wall  from  what 
it  was  when  the  trowel  first  settled  its  bricks.  The 
old  wall  has  a  past,  a  life,  a  story ;  as  Wordsworth 


60  STUDIES   IN   ANIMAL   LIFE. 

finely  says  of  the  mountain,  it  is  "  familiar  with  for- 
gotten years."  Not  only  are  there  obvious  traces 
of  age  in  the  crumbling  mortar  and  the  battered 
brick,  but  there  are  traces,  not  obvious  except  to 
the  inner  eye,  left  by  every  ray  of  light,  every  rain- 
drop, every  gust.  Nothing  perishes.  In  the  won- 
drous metamorphosis  momently  going  on  every 
where  in  the  universe,  there  is  change,  but  no  loss. 

Lest  you  should  imagine  this  to  be  poetry,  and 
not  science,  I  will  touch  on  the  evidence  that  every 
beam  of  light,  or  every  breath  of  air  which  falls 
upon  an  object,  permanently  affects  it.  In  photog- 
raphy we  see  the  effect  of  light  very  strikingly  ex- 
hibited; but  perhaps  you  wilt  object  that  this  proves 
nothing  more  than  that  light  acts  upon  an  iodized 
surface.  Yet,  in  truth,  light  acts  upon,  and  more  or 
less  alters  the  structure  of  every  object  on  which  it 
falls.  Nor  is  this  all.  If  a  wafer  be  laid  on  a  sur- 
face of  polished  metal,  which  is  then  breathed  upon, 
and  if,  when  the  moisture  of  the  breath  has  evapo- 
rated, the  wafer  be  shaken  off,  we  shall  find  that  the 
whole  polished  surface  is  not  as  it  was  before,  al- 
though our  senses  can  detect  no  difference ;  for  if 
we  breathe  again  upon  it,  the  surface  will  be  moist 
every  where  except  on  the  spot  previously  shelter- 
ed by  the  wafer,  which  will  now  appear  as  a  spec- 
tral image  on  the  surface.  Again  and  again  we 
breathe,  and  the  moisture  evaporates,  but  still  the 
spectral  wafer  reappears.  This  experiment  suc- 
ceeds after  a  lapse  of  many  months  if  the  metal  be 


STUDIES  IN   ANIMAL   LIFE.  6i 

carefully  put  aside  where  its  surface  can  not  be  dis- 
turbed. If  a  sheet  of  paper  on  which  a  key  has 
been  laid  be  exposed  for  some  minutes  to  the  sun- 
shine, and  then  instantaneously  viewed  in  the  dark, 
the  key  being  removed,  a  fading  spectre  of  the  key 
will  be  visible.  Let  this  paper  be  put  aside  for 
many  months  where  nothing  can  disturb  it,  and 
then  in  darkness  be  laid  on  a  plate  of  hot  metal, 
the  spectre  of  the  key  will  again  appear.  In  the 
case  of  bodies  more  highly  phosphorescent  than 
paper,  the  spectres  of  many  different  objects  which 
may  have  been  laid  on  in  succession  will,  on  warm- 
ing, emerge  in  their  proper  order.* 

This  is  equally  true  of  our  bodies  and  our  minds. 
We  are  involved  in  the  universal  metamorphosis. 
Nothing  leaves  us  wholly  as  it  found  us.  Every 
man  we  meet,  every  book  we  read,  every  picture 
or  landscape  we  see,  every  word  or  tone  we  hear, 
mingles  with  our  being  and  modifies  it.  There  are 
cases  on  record  of  ignorant  women,  in  states  of  in- 
sanity, uttering  Greek  and  Hebrew  phrases,  which 
in  past  years  they  had  heard  their  masters  utter, 
without,  of  course,  comprehending  them.  These 
tones  had  long  been  forgotten ;  the  traces  were  so 
faint  that  under  ordinary  conditions  they  were 'in- 
visible ;  but  the  traces  were  there,  and  in  the  in- 
tense light  of  cerebral  excitement  they  started  into 
prominence,  just  as  the  spectral  image  of  the  key 
started  into  sight  on  the  application  of  heat.  It  is 

*  DRAPER  :   Human  Physiology,  p.  288. 


62  STUDIES  IN   ANIMAL   LIFE. 

thus  with  all  the  influences  to  which  we  are  sub- 
jected. 

If  a  garden  wall  can  lead  our  vagabond  thoughts 
into  such  speculations  as  these,  surely  it  may  also 
furnish  us  with  matter  for  our  Studies  in  Animal 
Life.  Those  patches  of  moss  must  be  colonies. 
Suppose  we  examine  them.  I  pull  away  a  small 
bit,  which  is  so  dry  that  the  dust  crumbles  at  a 
touch ;  this  may  be  wrapped  in  a  piece  of  paper — 
dirt  and  all — and  carried  home.  Get  the  micro- 
scope ready,  and  now  attend. 

I  moisten  a  fragment  of  this  moss  with  distilled 
water.  Any  water  will  do  as  well,  but  the  use  of 
distilled  water  prevents  your  supposing  that  the 
animals  you  are  about  to  watch  were  brought  in  it, 
and  were  not  already  in  the  moss.  I  now  squeeze 
the  bit  between  my  fingers,  and  a  drop  of  the  con- 
tained water — somewhat  turbid  with  dirt — falls  on 
the  glass  slide,  which  we  may  now  put  on  the  mi- 
croscope stage.  A  rapid  survey  assures  us  that 
there  is  no  animal  visible.  The  moss  is  squeezed 
again,  and  this  time  little  yellowish  bodies  of  an 
irregular  oval  are  noticeable  among  the  particles 
of  dust  and  moss.  Watch  one  of  these,  and  pres- 
ently you  will  observe  a  slow  bulging  at  one  end, 
and  then  a  bulging  at  the  other  end.  The  oval 
has  elongated  itself  into  a  form  not  unlike  that- 
of  a  fat  caterpillar,  except  that  there  is  a  tapering 
at  one  end.  Now  a  forked  tail  is  visible ;  this  fixes 
on  to  the  glass,  while  the  body  swings  to  and  fro. 


STUDIES   IN   ANIMAL   LIFE. 


Now  the  head  is  drawn  in — as  if  it  were  swallowed 
— and  suddenly  in  its  place  are  unfolded  two  broad 
membranes,  having  each  a  circle  of  waving  cilia. 
The  lifeless  oval  has  become  a  living  animal !  You 
have  assisted  at  a  resuscitation,  not  from  death  by 
drowning,  but  by  drying:  the  animal  has  been 
drowned  into  life !  The  unfolded  membranes,  with 
their  cilia,  have  so  much  the  appearance  of  wheels 
that  the  name  of  "  "Wheel-bearer"  (Rotifera)  or 
"  Wheel  Animalcule"  has  been  given  to  the  animal. 


Fig.  16.— ROTTFEB  VULGABIB. 

A,  with  the  wheels  drawn  in  (at  c).  B,  with  the  wheels  expanded;  6,  eye 
ppots;  e,  jaw  and  teeth;  /,  alimentary  canal;  gr,  embryo;  A,  embryo  further 
developed :  ?',  water- vascular  system ;  fc,  vent. 


64  STUDIES   IN   ANIMAL   LIFE. 

The  Eotifera  (also,  and  more  correctly,  called 
Rotatoria)  form  an  interesting  study.  Let  us  glance 
at  their  organization : 

There  are  many  different  kinds  of  Kotifers,  vary- 
ing very  materially  in  size  and  shape,  the  males,  as 
was  stated  in  the  last  chapter,  being  more  imper- 
fectly organized  than  the  females.  They  may  be 
seen  either  swimming  rapidly  through  the  water 
by  means  of  the  vibratile  cilia  called  "  wheels,"  be- 
cause the  optical  effect  is  very  much  that  of  a 
toothed  wheel,  or  crawling  along  the  side  of  the 
glass,  fastening  to  it  by  the  head,  and  then  curving 
the  body  till  the  tail  is  brought  up  to  the  spot, 
which  is  then  fastened  on  by  the  tail,  and  the  head 
is  set  free.  They  may  also  be  seen  fastened  to  a 
weed,  or  the  glass,  by  the  tail,  the  body  waving  to 
and  fro,  or  thrusting  itself  straight  out,  and  setting 
the  wheels  in  active  motion.  In  this  attitude  the 
aspect  of  the  jaws  is  very  striking.  Leuwenhoek 
mistook  it  for  the  pulsation  of  a  heart,  which  its  in- 
cessant rhythm  much  resembles.  The  tail  and  the 
upper  part  of  the  body  have  a  singular  power  of 
being  drawn  out  or  drawn  in,  like  the  tube  of  a 
telescope.  There  is  sometimes  a  shell  or  carapace, 
but  often  the  body  is  covered  only  with  a  smooth 
firm  skin,  which,  however,  presents  decided  indica- 
tions of  being  segmented. 

The  first  person  who  described  these  Eotifers  was 
the  excellent  old  Leuwenhoek,*  and  his  animals 

*  LEUWENHOEK:  Select  Works,  ii.,  p.  210.  His  figures,  how- 
ever, are  very  incorrect. 


STUDIES   IN    ANIMAL   LIFE.  t>5 

were  got  from  the  gutter  of  a  house-top.  Since 
then  they  have  been  minutely  studied,  and  have 
been  shown  to"  be,  not  Infusoria,  as  Ehrenberg  im- 
agined, but  Crustacea.*  Your  attention  is  request- 
ed to  the  one  point  which  has  most  contributed  to 
the  celebrity  of  these  creatures — their  power  of  re- 
suscitation. Leuwenhoek  described — what  you 
have  just  witnessed,  namely — the  slow  resuscitation 
of  the  animal  (which  seemed  as  dry  as  dust,  and 
might  have  been  blown  about  like  any  particle  of 
dust)  directly  a  little  moisture  was  brought  to  it. 
Spallanzani  startled  the  world  with  the  announce- 
ment that  this  process  of  drying  and  moistening — 
of  killing  and  reviving — could  be  repeated  fifteen 
times  in  s accession;  so  that  the  Kotifer,  whose  nat- 
ural term  of  life  is  about  eighteen  days,  might,  it 
was  said,  be  dried  and  kept  for  years,  and  at  any 
time  revived  by  moisture.  That  which  seems  now 
no  better  than  a  grain  of  dust  will  suddenly  awaken 
to  the  energetic  life  of  a  complex  organism,  and 
may  again  be  made  as  dust  by  the  evaporation  of 
the  water. 

This  is  very  marvelous;  so  marvelous  that  a 
mind  trained  in  the  cultivated  caution  of  science 
will  demand  the  evidence  on  which  it  is  based. 
Two  months  ago  I  should  have  dismissed  the  doubt 
with  the  assurance  that  the  evidence  was  ample  and 

*  See  LEYDIG  :  Ueber  den  Bau  und  die  systematische  Stellung 
der  Rdderthiere,  in  SIEBOLD  und  KOLLIKER'S  Zeitschrift,  vi.,  and 
Ueber  Hydatina  Senta,  in  MULLER'S  Arr.hiv,  1857. 


66  STUDIES   IN   ANIMAL   LIFE. 

rigorous,  and  the  fact  indisputable;  for  not  only 
had  the  fact  been  confirmed  by  the  united  experi- 
ence of  several  investigators,  it  had  stood  the  test 
of  very  severe  experiment.  Thus,  in  1842,  M.  Do- 
yere  published  experiments  which  seemed  to  place 
it  beyond  skepticism.  Under  the  air-pump  he  set 
some  moss,  together  with  vessels  containing  sul- 
phuric acid,  which  would  absorb  every  trace  of 
moisture.  After  leaving  the  moss  thus  for  a  week, 
he  removed  it  into  an  oven,  the  temperature  of  which 
was  raised  to  300°  Fahrenheit.  Yet  even  this  treat- 
ment did  not  prevent  the  animals  from  resuscitating 
when  water  was  added. 

In  presence  of  testimony  like  this,  doubt  will  seem 
next  to  impossible.  Nevertheless,  my  own  experi- 
ments leave  me  no  choice  but  to  doubt.  Not  hav- 
ing witnessed  M.  Doyere's  experiment,  I  ani  not 
prepared  to  say  wherein  its  fallacy  lies ;  but  that 
there  is  a  fallacy  seems  to  me  capable  of  decisive 
proof.  In  M.  Pouchet's  recent  work*  I  first  read  a 
distinct  denial  of  the  pretended  resuscitation  of  the 
Eotifers ;  this  denial  was  the  more  startling  to  me, 
because  I  had  myself  often  witnessed  the  reawaken- 
ing of  these  dried  animals.  Nevertheless,  whenev- 
er a  doubt  is  fairly  started,  we  have  not  done  jus- 
tice to  it  until  we  have  brought  it  to  the  test  of  ex- 
periment; accordingly,  I  tested  this,  and  quickly 
came  upon  what  seems  to  me  the  source  of  the  gen- 

*  POUCHET  :  Heterogenie,  ou  Traite  de  la  Generation  Spontanee, 
1859,  p.  453. 


STUDIES   IN   ANIMAL   LIFE.  67 

eral  misconception.  Day  after  day  experiments 
were  repeated,  varied,  and  controlled,  and  with  re- 
sults so  unvarying  that  hesitation  vanished ;  and  as 
some  of  these  experiments  are  of  extreme  simplici- 
ty, you  may  verify  what  I  say  with  little  trouble. 
Squeeze  a  drop  from  the  moss,  taking  care  that 
there  is  scarcely  any  dirt  in  it ;  and,  having  ascer- 
tained that  it  contains  Eotifers  or  Tardigrades,* 
alive  and  moving,  place  the  glass  slide  under  a  bell- 
glass,  to  shield  it  from  currents  of  air,  and  there  al- 
low the  water  to  evaporate  slowly,  but  completely, 
by  means  of  chloride  of  calcium  or  sulphuric  acid 
placed  under  the  bell-glass;  or,  what  is  still  sim- 
pler, place  a  slide  with  the  live  animals  on  the  man- 
telpiece when  a  fire  is  burning  in  the  grate.  If  on 
the  day  following  you  examine  this  perfectly  dry 
glass,  you  will  see  the  contracted  bodies  of  the  Eo- 
tifers, presenting  the  aspect  of  yellowish  oval  bodies; 
but  attempt  to  resuscitate  them  by  the  addition  of 
a  little  fresh  water,  and  you  will  find  that  they  do 
not  revive,  as  they  revived  when  dried  in  the  moss ; 
they  sometimes  swell  a  little,  and  elongate  them- 
selves, and  you  imagine  this  is  a  commencement  of 
resuscitation;  but  continue  watching  for  two  or 
-three  days,  and  you  will  find  it  goes  no  further. 

*  The  Tardigrade,  or  microscopic  Sloth,  belongs  to  the  order  of 
Arachnida,  and  is  occasionally  found  in  moss,  stagnant  ponds,  etc. 
I  have  only  met  with  four  specimens  in  all  my  investigations,  and 
they  were  all  found  in  moss.  SPALLANZANI  described  and  figured 
it  (very  badly),  and  M.  DOYEEE  has  given  a  fuller  description  in 
the  Annaks  des  Sciences,  2d  series,  vols.  xiv.,  xvii.,  and  xviii. 


68  STUDIES   IN   ANIMAL    LIFE. 

Never  do  these  oval  bodies  become  active  crawling 
Eotifers;  never  do  they  expand  their  wheels,  and 
set  the  oesophagus  at  work.  No ;  the  Kotifer  once 
dried  is  dead,  and  dead  forever. 

But  if,  like  a  cautious  experimenter,  you  vary 
and  control  the  experiment,  and  beside  the  glass 
slide  place  a  watch-glass  containing  Eotifers  with 
dirt  or  moss,  you  will  find  that  the  addition  of  wa- 
ter to  the  contents  of  the  watch-glass  will  often  (not 
always)  revive  the  animals.  What  you  can  not  ef- 
fect on  a  glass  slide  without  dirt,  or  with  very  little, 
you  easily  effect  in  a  watch-glass  with  dirt  or  moss ; 
and  if  you  give  due  attention  you  will  find  that  in 
each  case  the  result  depends  upon  the  quantity  of 
the  dirt.  And  this  leads  to  a  clear  understanding 
of  the  whole  mystery ;  this  reconciles  the  conflict- 
ing statements.  The  reason  why  Eotifers  ever  re- 
vive is  because  they  have  not  been  dried— they 
have  not  lost  by  evaporation  that  small  quantity 
of  water  which  forms  an  integral  constituent  of  their 
tissues;  and  it  is  the  presence  of  dirt  or  moss  which 
prevents  this  complete  evaporation.  No  one,  I  sup- 
pose, believes  that  the  Eotifer  actually  revives  after 
once  being  dead.  If  it  has  a  power  of  remaining  in 
a  state  of  suspended  animation,  like  that  of  a  frozen 
frog,  it  can  do  so  only  on  the  condition  that  its  or- 
ganism is  not  destroyed;  and  destroyed  it  would 
be  if  the  water  were  removed  from  its  tissues ;  for, 
strange  as  it  may  seem,  water  is  not  an  accessory, 
but  a  constituent  element  of  every  tissue;  and  this 


STUDIES   IN   ANIMAL   LIFE.  69 

can  not  be  replaced  mechanically — it  can  only  be 
replaced  by  vital  processes.  Every  one  who  has 
made  microscopic  preparations  must  be  aware  that 
when  once  a  tissue  is  desiccated,  it  is  spoiled;  it 
will  not  recover  its  form  and  properties  on  the  ap- 
plication of  water,  because  the  water  was  not  orig- 
inally worked  into  the  web  by  a  mere  process  of 
imbibition — like  water  in  a  sponge — but  by  a  molec- 
ular process  of  assimilation,  like  albumen  in  a  mus- 
cle. Therefore  I  say  that  desiccation  is  necessarily 
.death,  and  the  Eotifer  which  revives  can  not  have 
been  desiccated.  This  being  granted,  we  have  only 
to  ask,  "What  prevents  the  Eotifer  from  becoming 
completely  dried  ?  Experiment  shows  that  it  is  the 
presence  of  dirt  or  moss  which  does  this.  The 
whole  marvel  of  the  Eotifer's  resuscitation,  there- 
fore, amounts  to  this :  that  if  the  water  in  which  it 
lives  be  evaporated,  the  animal  passes  into  a  state 
of  suspended  animation,  and  remains  so  as  long  as 
its  own  water  is  protected  from  evaporation. 

I  am  aware  that  this  is  not  easily  to  be  reconciled 
with  M.  Doyere's  experiment,  since  the  application 
of  a  temperature  so  high  as  300°  Fahrenheit  (nearly 
a  hundred  degrees  above  boiling  water)  must,  one 
would  imagine,  have  completely  desiccated  the  ani- 
mals, in  spite  of  any  amount  of  protecting  dirt.  It 
is  possible  that  M.  Doyere  may  have  mistaken  that 
previously-noticed  swelling  up  of  the  bodies,  on  the 
application  of  water,  for  a  return  to  vital  activity. 
Tf  not,  I  am  at  a  loss  to  explain  the  contradiction ; 


70  STUDIES  IN   ANIMAL   LIFE. 

for  certainly  in  my  experience  a  much  more  mod- 
erate desiccation — namely,  that  obtained  by  simple 
evaporation  over  a  mantelpiece  or  under  a  large 
bell-glass — always  destroyed  the  animals  if  little  or 
no  dirt  were  present. 

The  subject  has  recently  been  brought  before  the 
French  Academy  of  Sciences  by  M.  Davaine,  whose 
experiments*  lead  him  to  the  conclusion  that  those 
Rotifers  which  habitually  live  in  ponds  will  not  re- 
vive after  desiccation,  whereas  those  which  live  in 
moss  always  do  so.  I  believe  the  explanation  to  be 
this :  the  Rotifers  living  in  ponds  are  dried  without 
any  protecting  dirt  or  moss,  and  that  is  the  reason 
they  do  not  revive. 

After  having  satisfied  myself  on  this  point,  I  did 
what  perhaps  would  have  saved  me  some  trouble 
if  thought  of  before.  I  took  down  Spallanzani,  and 
read  his  account  of  his  celebrated  experiments.  To 
my  surprise  and  satisfaction,  it  appeared  that  he 
had  accurately  observed  the  same  facts,  but  curious- 
ly missed  their  real  significance.  Nothing  can  be 
plainer  than  the  following  passage :  "  But  there  is 
one  condition  indispensable  to  the  resurrection  of 
wheel-animals :  it  is  absolutely  necessary  that  there 
should  be  a  certain  quantity  of  sand;  without  it 
they  will  not  revive.  One  day  I  had  two  wheel- 
animals  traversing  a  drop  of  water  about  to  evapo- 
rate which  contained  very  little  sand.  •  Three  quar- 
ters of  an  hour  after  evaporation  they  were  dry  and 

*  DAVAINE  in  Annales  des  Sciences  Naturelles,  1858,  x.,  p.  335. 


STUDIES  IN  ANIMAL   LIFE.  71 

motionless.  I  moistened  them  with  water  to  revive 
them,  but  in  vain,  notwithstanding  that  they  were 
immersed  in  water  many  hours.  Their  members 
swelled  to  thrice  the  original  size,  but  they  remain- 
ed motionless.  To  ascertain  whether  the  fact  was 
accidental,  I  spread  a  portion  of  sand,  containing 
animals,  on  a  glass  slide,  and  waited  until  it  became 
dry  in  order  to  wet  it  anew.  The  sand  was  care- 
lessly scattered  on  the  glass,  so  as  to  be  a  thin  cov- 
ering on  some  parts,  and  on  others  in  a  very  small 
quantity :  here  the  animals  did  not  revive ;  but  all 
that  were  in  those  parts  with  abundance  of  sand  re- 
vived."* He  further  says  that  if  sand  be  spread 
out  in  considerable  quantities  in  some  places,  much 
less  in  others,  and  very  little  in  the  rest,  on  moist- 
ening it  the  revived  animals  will  be  numerous  in 
the  first,  less  numerous  in  the  second,  and  none  at 
all  in  the  third. 

It  is  not  a  little  remarkable  that  observations  so 
precise  as  these  should  have  for  many  years  passed 
unregarded,  and  not  led  to  the  true  explanation  of 
the  mystery.  Perhaps  an  inherent  love  of  the  mar- 
velous made  men  greedily  accept  the  idea  of  resus- 
citation, and  indisposed  them  to  attempt  an  expla- 
nation of  it.  Spallanzani's  own  attempt  is  certainly 
not  felicitous.  He  supposes  that  the  dust  prevents 
the  lacerating  influence  of  the  air  from  irritating  and 
injuring  the  animals.  And  this  explanation  is  ac- 
cepted by  his  translator. 

*  SPALLAKZAKI:  Tracts  on  the  Natural  History  of  Animals  and 
Vegetable*:  translated  by  Dalyell,  ii.,  p.  129. 


72  STUDIES  IN   ANIMAL   LIFE. 

[Since  the  foregoing  remarks  were  in  type,  M. 
Gavarret  has  published  (Annales  des  Sciences  Natu- 
relles,  1859,  xi.,  p.  315)  the  account  of  his  experi- 
ments on  Eotifers  and  Tardigrades,  in  which  he 
found  that  after  subjecting  the  moss  to  a  desiccation 
the  most  complete  according  to  our  present  means, 
the  animals  revived  after  twenty -four  hours'  immer- 
sion of  the  moss  in  water.  This  result  seems  flatly 
to  contradict  the  result  I  arrived  at,  but  only  seems 
to  contradict  it,  for  in  my  experiments  the  animals, 
not  the  moss,  were  subjected  to  desiccation.  Nev- 
ertheless, I  confess  that  my  confidence  was  shaken 
by  experiments  so  precise,  and  performed  by  so  dis- 
tinguished an  investigator,  and  I  once  more  resumed 
the  experiments,  feeling  persuaded  that  the  detec- 
tion of  the  fallacy,  wherever  it  might  be,  would  be 
well  worth  the  trouble.  The  results  of  these  con- 
trolling experiments  are  all  I  can  find  room  for 
here :  Whenever  the  animals  were  completely  separated 
from  the  dirt,  they  perished ;  in  two  cases  there  was 
a  very  little  dirt — a  mere  film,  so  to  speak — in  the 
watch-glass  and  glass  cell,  and  this,  slight  as  it  was, 
sufficed  to  protect  two  out  of  eight,  and  three  out 
of  ten  Eotifers,  which  revived  on  the  second  day ; 
the  others  did  not  revive  even  on  the  third  day  aft- 
er their  immersion.  In  one  instance,  a  thin  cover- 
ing-glass was  placed  over  the  water  on  the  slide, 
and  the  evaporation  of  the  water  seemed  complete, 
yet  this  glass  cover  sufficed  to  protect  a  Eotifer, 
which  revived  in  three  hours. 


STUDIES   IN   ANIMAL   LIFE.  73 

If  we  compare  these  results  with  those  obtained 
by  M.  Davaine,  we  can  scarcely  avoid  the  conclusion 
that  it  is  only  when  the  desiccation  of  the  Eotifers 
is  prevented  by  the  presence  of  a  small  quantity  of 
moss  or  of  dirt — between  the  particles  of  which  they 
find  shelter — that  they  revive  on  the  application  of 
water.  And  even  in  the  severe  experiments  of  M. 
Doyere  and  M.  Gavarret,  some  of  the  animals  must 
have  been  thus  protected  ;  and  I  call  particular  at- 
tention to  the  fact  that,  although  some  animals  re- 
vived, others  always  perished.  But  if  the  organiza- 
tion of  the  Kotifer  or  Tardigrade  is  such  that  it  can 
withstand  desiccation — if  it  only  needs  the  fresh  ap- 
plication of  moisture  to  restore  its  activity — all,  or 
almost  all  the  animals  experimented  on  ought  to 
revive ;  and  the  fact  that  only  some  revive  leads  us 
to  suspect  that  these  have  not  been  desiccated — a 
suspicion  which  is  warranted  by  direct  experiments. 
I  believe,  then,  that  the  discrepancy  amounts  to 
this :  investigators  who  have  desiccated  the  moss 
containing  animals  find  some  of  the  animals  revive 
on  the  application  of  moisture,  but  those  who  desic- 
cate the  animals  themselves  will  find  no  instances 
of  revival.] 

The  time  spent  on  these  Eotifers  will  not  have 
been  misspent  if  it  has  taught  us  the  necessity  of 
caution  in  all  experimental  inquiries.  Although 
experiment  is  valuable — nay,  indispensable — as  a 
means  of  interrogating  Nature,  it  is  constantly  lia- 
ble to  mislead  us  into  the  idea  that  we  have  rightly 
D 


74  STUDIES   IN  ANIMAL   LIFE. 

interrogated  and  rightly  interpreted  the  replies; 
and  this  danger  arises  from  the  complexity  of  the 
cases  with  which  we  are  dealing,  and  our  proneness 
to  overlook  or  disregard  some  seemingly  trifling 
condition — a  trifle  which  may  turn  out  of  the  ut- 
most importance.  The  one  reason  why  the  study 
of  science  is  valuable  as  a  means  of  culture,  over 
and  above  its  own  immediate  objects,  is  that  in  it 
the  mind  learns  to  submit  to  realities  instead  of 
thrusting  its  figments  in  the  place  of  realities — en- 
deavors to  ascertain  accurately  what  the  order  of 
Nature  w,  and  not  what  it  ought  to  be  or  might  be. 
The  one  reason  why,  of  all  sciences,  Biology  is  pre- 
eminent as  a  means  of  culture,  is,  that,  owing  to  the 
great  complexity  of  all  the  cases  it  investigates,  it 
familiarizes  the  mind  with  the  necessity  of  attend- 
ing to  all  the  conditions,  and  it  thus  keeps  the  mind 
alert.  It  cultivates  caution,  which,  considering  the 
tendency  there  is  in  men  to  "  anticipate  Nature,"  is 
a  mental  tonic  of  inestimable  worth.  I  am  far  from 
asserting  that  biologists  are  more  accurate  reasoners 
than  other  men ;  indeed,  the  mass  of  crude  hypoth- 
esis which  passes  unchallenged  by  them  is  against 
such  an  idea.  But,  whether  its  advantage  be  used 
or  neglected,  the  truth  nevertheless  is,  that  Biology, 
from  the  complexity  of  its  problems,  and  the  ne- 
cessity of  incessant  verification  of  its  details,  offers 
greater  advantages  for  culture  than  any  other  branch 
of  science. 

I  have  once  or  twice  mentioned  the  words  Mol- 


s^pTupJ^ 

vv    or  TfeE      ifr 


OF  TfcE 
STUDIES  IN   ANIMAL 


lusk  and  Crustacean,  to  which  the 
with  the  language  of  Natural  History  wirl  have  at 
tached  but  vague  ideas ;  and  although  I  wanted  to 
explain  these,  and  convey  a  distinct  conception  of 
the  general  facts  of  classification,  it  would  have 
been  too  great  an  interruption.  So  I  will  here 
make  an  opportunity,  and  finish  the  chapter  with 
an  indication  of  the  five  types,  or  plans  of  struct- 
ure, under  one  of  which  every  animal  is  classed. 
Without  being  versed  in  science,  you  discern  at 
once  whether  the  book  before  you  is  mathematical, 
physical,  chemical,  botanical,  or  physiological.  In 
like  manner,  without  being  versed  in  Natural  His- 
tory, you  ought  to  know  whether  the  animal  be- 
fore you  belongs  to  the  Yertebrata,  Mollusca,  Artic- 
ulata,  Kadiata,  or  Protozoa. 

A  glance  at  the  contents  of  our  glass  vases  will 
yield  us  samples  of  each  of  these  five  divisions  of 
the  animal  kingdom.  We  begin  with  this  Triton 
(Fig.  17).  It  is  a  representative  of  the  VERTEBRATE 
division  or  sub-kingdom.  You  have  merely  to  re- 
member that  it  possesses  a  backbone  and  an  inter- 
nal skeleton,  and  you  will  at  once  recognize  the 
cardinal  character  which  makes  this  Triton  range 
under  the  same  general  head  as  men,  elephants, 
whales,  birds,  reptiles,  or  fishes.  All  these,  in  spite 
of  their  manifold  differences,  have  this  one  charac- 
ter in  common — they  are  all  backboned ;  they  have 
all  an  internal  skeleton;  they  are  all  formed  ac- 
cording to  one  general  tvpe.  In  all  vertebrate  ani- 


76 


STUDIES  IN  ANIMAL  LIFE. 


Fig.  17.— MALE  TBITON,  OR  WATEB-NEWT. 

mals  the  skeleton  is  found  to  be  identical  in  plan. 
Every  bone  in  the  body  of  a  triton  has  its  corre- 
sponding bone  in  the  body  of  a  man  or  of  a  mouse ; 
and  every  bone  preserves  the  same  connection  with 
other  bones,  no  matter  how  unlike  may  be  the  va- 
rious limbs  in  which  we  detect  its  presence.  Thus, 
widely  as  the  arm  of  a  man  differs  from  the  fin  of 
a  whale,  or  the  wing  of  a  bird,  or  the  wing  of  a  bat, 
or  the  leg  of  a  horse,  the  same  number  of  bones, 
and  the  same  connections  of  the  bones,  are  found  in 
each.  A  fin  is  one  modified  form  of  the  typical 
limb ;  an  arm  is  another ;  a  wing  another.  That 
which  is  true  of  the  limbs  is  also  true  of  all  the 
other  organs;  and  it  is  on  this  ground  that  we 
speak  of  the  vertebrate  type.  From  fish  to  man 


STUDIES   IN   ANIMAL   LIFE.  77 

one  common  plan  of  structure  prevails,  and  the 
presence  of  a  backbone  is  the  index  by  which  to 
recognize  this  plan. 

The  Triton  has  been  wriggling  grotesquely  in 
our  grasp  while  we  have  made  him  our  text,  and, 
now  he  is  restored  to  his  vase,  plunges  to  the  bot- 
tom with  great  satisfaction  at  his  escape.  This  wa- 
ter-snail, crawling  slowly  up  the  side  of  the  vase, 
and  cleaning  it  of  the  green  growth  of  microscopic 
plants,  which  he  devours,  shall  be  our  representa- 
tive of  the  second  great  division — the  MOLLUSCA. 
I  can  not  suggest  any  obvious  character  so  distinct- 
ive as  a  backbone  by  which  the  word  mollusk  may 
at  once  call  up  an  idea  of  the  type  which  prevails 
in  the  group.  It  won't  do  to  say  "  shellfish,"  be- 
cause many  mollusks  have  no  shells,  and  many  ani- 
mals which  have  shells  are  not  mollusks.  The 
name  was  originally  bestowed  on  account  of  the 
softness  of  the  animals.  But  they  are  not  softer 
than  worms,  and  much  less  so  than  jellyfish.  You 
may  know  that  snails  and  slugs,  oysters  and  cuttle- 
fish, are  mollusks ;  but  if  you  want  some  one  char- 
acter by  which  the  type  may  be  remembered,  you 
must  fix  on  the  imperfect  symmetry  of  the  mol- 
lusk's  organs.  I  say  imperfect  symmetry,  because  it 
is  an  error,  though  a  common  one,  to  speak  of  the 
mollusk's  body  not  being  bilateral — that  is  to  say,  of 
its  not  being  composed  of  two  symmetrical  halves. 
A  vertebrate  animal  may  be  divided  lengthwise, 
and  each  half  will  closely  resemble  the  other ;  the 


78  STUDIES  IN   ANIMAL   LIFE. 

backbone  forms,  as  it  were,  an  axis,  on  either  side 
of  which  the  organs  are  disposed ;  but  the  mollusk 
is  said  to  have  no  such  axis,  no  such  symmetry.  I 
admit  the  absence  of  an  axis,  but  I  deny  the  total 
absence  of  symmetry.  Many  of  its  organs  are  as 
symmetrical  as  those  of  a  vertebrate  animal — i.  e., 
the  eyes,  the  feelers,  the  jaws — and  the  gills  in  Cut- 
tlefish, Eolids,  and  Pteropods ;  while,  on  the  other 
hand,  several  organs  in  the  vertebrate  animal  are  as 
asymmetrical  as  any  of  those  in  the  mollusk — i.  e., 
the  liver,  spleen,  pancreas,  stomach,  and  intestines.* 
As  regards  bilateral  structure,  therefore,  it  is  only 
a  question  of  degree.  The  vertebrate  animal  is  not 
entirely  symmetrical,  nor  is  the  mollusk  entirely 
unsymmetrical.  But  there  is  a  characteristic  dis- 
position of  the  nervous  system  peculiar  to  mol- 
lusks :  it  neither  forms  an  axis  for  the  body,  as  it 
does  in  the  Yertebrata  and  Articulata,  nor  a  centre, 
as  it  does  in  the  Eadiata,  but  is  altogether  irregular 
and  unsymmetrical.  This  will  be  intelligible  from 
the  following  diagram  of  the  nervous  systems  of  a 
mollusk  and  an  insect,  with  which  that  of  a  starfish 
may  be  compared  (Fig.  18).  Here  you  perceive 
how  the  nervous  centres  and  the  nerves  which 

*  In  some  cases  of  monstrosity  these  organs  are  transposed,  the 
liver  being  on  the  left,  and  the  pancreas  on  the  right  side.  It  was 
in  allusion  to  a  case  of  this  kind,  then  occupying  the  attention  of 
Paris,  that  MOLIERE  made  his  Mededn  malgre  Lui  describe  the 
heart  as  on  the  right  side,  the  liver  on  the  left ;  on  the  mistake  be- 
ing noticed,  he  replies,  "  Oui,  autrefois ;  mais  nous  avons  change 
tout  cela." 


STUDIES   IN   ANIMAL   LIFE. 


79 


Fig.  18.— NERVOUS  SYSTEM  OP  SEA-HABE  (A)  and  CENTIPEDE  (B). 


Fig.  19. — NERVOUS  SYSTEM  OF  STARFISH. 


80  STUDIES   IN   ANIMAL   LIFE. 

issue  from  them  are  irregularly  disposed  in  the 
mollusks,  and  symmetrically  in  the  insect. 

But  the  recognition  of  a  mollusk  will  be  easier 
when  you  have  learned  to  distinguish  it  from  one 
of  the  AETICULATA,  forming  the  third  great  divi- 
sion— the  third  animal  type.  Of  these,  our  vases 
present  numerous  representatives — prawns,  beetles, 
water-spiders,  insect-larvae,  entomostraca,  and  worms. 
There  is  a  very  obvious  character  by  which  these 
may  be  recognized :  they  have  all  bodies  composed 
of  numerous  segments,  and  their  limbs  are  jointed, 
and  they  have  mostly  an  external  skeleton  from 
which  their  limbs  are  developed.  Sometimes  the 
segments  of  their  bodies  are  numerous,  as  in  the 
centipede,  lobster,  etc. ;  sometimes  several  segments 
are  fused  together,  as  in  the  crab ;  and  sometimes, 
as  in  worms,  they  are  indicated  by  slight  markings 
or  depressions  of  the  skin,  which  give  the  appear- 
ance of  little  rings,  and  hence  the  worms  have  been 
named  Annelida,  or  Annulata,  or  Annulosa.  In  these 
last-named  cases  the  segmental  nature  of  the  type  is 
detected  in  the  fact  that  the  worms  grow,  segment 
by  segment ;  and  also  by  the  fact  that-  in  most  of 
them  each  segment  has  its  own  nerves,  heart,  stom- 
ach, etc. — each  segment  is,  in  fact,  a  zooid.* 

Just  as  we  recognize  a  vertebrate  by  the  presence 
of  a  backbone  and  internal  skeleton,  we  recognize 
an  articulate  by  its  jointed  body  and  external  skele- 
ton. In  both,  the  nervous  system  forms  the  axis 

*  The  term  zooid  was  explained  in  our  last  chapter. 


•STUDIES   IN   ANIMAL   LIFE.  81 

of  the  body.  The  Mollusk,  on  the  contrary,  has  no 
skeleton,  internal  or  external,*  and  its  nervous  sys- 
tem does  not  form  an  axis.  As  a  rule,  both  verte- 
brates and  articulates  have  limbs,  although  there 
are  exceptions  in  serpents,  fishes,  and  worms.  The 
Mollusks  have  no  limbs.  Backboned,  jointed,  and 
non-jointed,  therefore,  are  the  three  leading  charac- 
teristics of  the  three  types. 

Let  us  now  glance  at  the  fourth  division — the 
EADIATA,  so  called  because  of  the  disposition  of  the 
organs  round  a  centre,  which  is  the  mouth.  Our 
fresh- water  vases  afford  us  only  one  representative 
of  this  type — the  Hydra,  or  fresh-water  Polype, 
whose  capture  was  recorded  in  the  last  chapter.  Is 
it  not  strange  that  while  all  the  Kadiata  are  aquatic, 
not  a  single  terrestrial  representative  having  been 
discovered,  only  one  should  be  found  in  fresh  wa- 
ter? Think  of  the  richness  of  the  seas,  with  their 
hosts  of  Polypes,  Actiniae,  Jellyfish,  Starfishes,  Sea- 
urchins,  Sea-pens  (Pennatulce),  Lily -stars  (Comatu- 
Ice),  and  Sea-cucumbers  (Rolothurice),  and  then  com- 
pare the  poverty  of  rivers,  lakes,  and  ponds,  re- 
duced to  their  single  representative,  the  Hydra. 
The  radiate  structure  may  best  be  exhibited  by  the 
diagram  of  the  nervous  system  of  the  Starfishf  on 
page  79. 

*  In  the  cuttlefish  there  is  the  commencement  of  an  internal 
skeleton  in  the  cartilage-plates  protecting  the  brain. 

+  It  is  right  to  add  that  there  are  serious  doubts  entertained  re- 
specting the  claim  of  a  starfish  to  the  possession  of  a  nervous  sys- 

D2 


82  STUDIES   IN    ANIMAL    LIFE. 

Cuvier,  to  whom  we  owe  this  classification  of  the 
animal  kingdom  into  four  great  divisions,  would 
have  been  the  first  to  recognize  the  chaotic  con- 
dition in  which  he  left  this  last  division,  and  would 
have  acquiesced  in  the  separation  of  the  PROTOZOA, 
which  has  since  been  made.  This  fifth  division  in- 
cludes many  of  the  microscopic  animals  known  as 
Infusoria,  and  receives  its  name  from  the  idea  that 
these  simplest  of  all  animals  represent,  as  it  were, 
the  beginnings  of  life.* 

But  Cuvier's  arrangement  is  open  to  a  more  se- 
rious objection.  The  state  of  science  in  his  day 
excused  the  imperfection  of  classing  the  Infusoria 
and  parasites  under  the  Eadiata ;  but  it  was  owing,  I 
conceive,  to  an  unphilosophical  view  of  morphology 
that  he  placed  the  mollusks  next  to  the  Yertebrata, 
instead  of  placing  the  Articulata  in  that  position. 
He  was  secretly  determined  by  the  desire  to  show 
that  there  are  four  very  distinct  types,  or  plans  of 
structure,  which  can  not  by  any  transitions  be 
brought  under  one  law  of  development.  Lamarck 
and  Geoffroy  St.  Hilaire  maintained  the  idea  of  uni- 
ty of  composition  throughout  the  animal  kingdom : 
in  other  words,  that  all  the  varieties  of  animal  forms 
were  produced  by  successive  modifications ;  and 
several  of  the  German  naturalists  maintained  that 
the  vertebrata  in  their  embryonic  stages  passed 

tern  at  all ;  but  the  radiate  structure  is  represented  in  the  diagram, 
as  it  also  is,  very  clearly,  in  a  Sea-anemone. 

*  Protozoa,  from  proton,  first,  and  zoon,  animal. 


STUDIES   IN   ANIMAL    LIFE.  S3 

through,  forms  which  were  permanent  in  the  lower 
animals.  This  idea  Cuvier  always  opposed.  He 
held  that  the  four  types  were  altogether  distinct; 
and  by  his  arrangement  of  them,  their  distinctness 
certainly  appears  much  greater  than  would  be  the 
case  on  another  arrangement.  But,  without  dis- 
cussing this  question  here,  it  is  enough  to  point  out 
the  fact  of  the  enormous  superiority  in  intelligence, 
in  sociality,  and  in  complexity  of  animal  functions 
which  insects  and  spiders  exhibit  when  compared 
with  the  highest  of  the  mollusks,  to  justify  the  re- 
moval of  the  mollusca,  and  the  elevation  of  the  ar- 
ticulata  to  the  second  place  in  the  animal  hierarchy. 
Nor  is  this  all.  If  we  divide  animals  into  four 
groups,  these  four  naturally  dispose  themselves  into 
two  larger  groups:  the  first  of  these,  comprising 
Vertebrata  and  Articulata,  is  characterized  by  a 
nervous  axis  and  a  skeleton  ;  the  second,  comprising 
Mollusca  and  Eadiata,  is  characterized  by  the  ab- 
sence of  both  nervous  axis  and  skeleton.  It  is  ob- 
vious that  a  bee  much  more  closely  resembles  a 
bird  than  any  mollusk  resembles  any  vertebrate. 
If  there  are  many  and  important  differences  be- 
tween the  vertebrate  and  articulate  types,  there  are 
also  many  and  important  resemblances ;  if  the  nerv- 
ous axis  is  above  the  viscera,  and  forms  the  dorsal 
line  of  the  vertebrate,  whereas  it  is  underneath  the 
viscera,  and  forms  the  ventral  line  in  the  articulate, 
it  is,  nevertheless,  in  both,  the  axis  of  the  body,  and 
in  both  it  sends  off  nerves  to  supply  symmetrical 


84  STUDIES  IN   ANIMAL   LIFE. 

limbs ;  in  both  it  has  similar  functions.  And  while 
the  articulata  thus  approach  in  structure  the  verte- 
brate type,  the  mollusca  are  not  only  removed  from 
that  type  by  many  diversities,  but  a  number  of  them 
have  such  affinities  with  the  Eadiate  type  that  it  is 
only  in  quite  recent  days  that  the  whole  class  of 
Polyzoa  (or  Bryozoa,  as  they  are  also  called)  has 
been  removed  from  the  Eadiata,  and  ranged  under 
the  Mollusca. 

To  quit  this  topic,  and  recur  once  more  to  the 
five  divisions,  we  have  only  the  broad  outlines  of 
the  picture  in  Yertebrata,  Mollusca,  Articulata,  Ea- 
diata, and  Protozoa ;  but  this  is  a  good  beginning, 
and  we  can  now  proceed  to  the  further  subdivisions. 
Each  of  these  five  sub-kingdoms  is  divided  into 
classes;  these,  again,  into  orders;  these  into  fami- 
lies; these  into  genera;  these  into  species;  and 
these,  finally,  into  varieties.  Thus,  suppose  a  dwarf 
terrier  is  presented  to  us  with  a  request  that  we 
should  indicate  its  various  titles  in  the  scheme  of 
classification :  we  begin  by  calling  it  a  vertebrate ; 
we  proceed  to  assign  its  class  as  the  mammalian ; 
its  order  is  obviously  that  of  the  carnivora ;  its 
family  is  that  of  the  fox,  wolf,  jackal,  etc.,  named 
Canidce ;  its  genus  is,  of  course,  that  of  Canis ;  its 
species,  terrier;  its  variety,  dwarf  terrier.  Inas- 
much as  all  these  denominations  are  the  expres- 
sions of  scientific  research,  and  not  at  all  arbitrary 
or  fanciful,  they  imply  an  immense  amount  of  labor 
and  sagacity  in  their  establishment ;  and  when  we 


{STUDIES   IN   ANIMAL   LIFE.  85 

remember  that  naturalists  have  thus  classed  upward 
of  half  a  million  of  distinct  species,  it  becomes  an 
interesting  inquiry,  What  has  been  -the  guiding 
principle  of  this  successful  labor?  on  what  basis  is 
so  large  a  superstructure  raised  ?  This  question  we 
shall  answer  in  the  next  chapter. 


STUDIES   IN    ANIMAL   LIFE. 


CHAPTER  IV. 

An  extinct  Animal  recognized  by  its  Tooth  :  how  came  this  to  be 
possible  ? — The  Task  of  Classification. — Artificial  and  natural 
Methods. — Linnaeus,  and  his  Baptism  of  the  Animal  Kingdom: 
his  Scheme  of  Classification. — What  is  there  underlying  all 
true  Classification? — The  chief  Groups. — What  is  a  Species? — 
Restatement  of  the  Question  respecting  the  Fixity  or  Variability 
of  Species. — The  two  Hypotheses. — Illustration  drawn  from  the 
Romance  Languages.— Caution  to  Disputants. 

I  WAS  one  day  talking  with  Professor  Owen  in  the 
Hunterian  Museum,  when  a  gentleman  approached 
with  a  request  to  be  informed  respecting  the  nature 
of  a  curious  fossil  which  had  been  dug  up  by  one 
of  his  workmen.  As  he  drew  the  fossil  from  a 
small  bag,  and  was  about  to  hand  it  for  examina- 
tion, Owen  quietly  remarked,  "  That  is  the  third 
molar  of  the  under  jaw  of  an  extinct  species  of  rhi- 
noceros." The  astonishment  of  the  gentleman  at 
this  precise,  and  confident  description  of  the  fossil, 
before  even  it  had  quitted  his  hands,  was  doubtless 
very  great.  I  know  that  mine  was,  until  the  reflec- 
tion occurred  that  if  some  one,  little  acquainted  with 
editions,  had  drawn  a  volume  from  his  pocket,  de- 
claring he  had  found  it  in  an  old  chest,  any  biblio- 
phile would  have  been  able  to  say  at  a  glance, 
"That  is  an  Elzevir;"  or,  "That  is  one  of  the 
Tauchnitz  classics,  stereotyped  at  Leipzig."  Owen 
is  as  familiar  with  the  aspect  of  the  teeth  of  ani- 


STUDIES   IN   ANIMAL   LIFE.  87 

raals,  living  and  extinct,  as  a  student  is  with  the  as- 
pect of  editions.  Yet,  before  that  knowledge  could 
have  been  acquired,  before  he  could  say  thus  confi- 
dently that  the  tooth  belonged  to  an  extinct  species 
of  rhinoceros,  the  united  labors  of  thousands  of  dili- 
gent inquirers  must  have  been  directed  to  the  clas- 
sification of  animals.  How  could  he  know  that  the 
rhinoceros  was  of  that  particular  species  rather  than 
another  ?  and  what  is  meant  by  species  ?  To  trace 
the  history  of  this  confidence  would  be  to  tell  the 
long  story  of  zoological  investigation ;  a  story  too 
long  for  narration  here,  though  we  may  pause  a 
while  to  consider  its  difficulties. 

To  make  a  classical  catalogue  of  the  books  in  the 
British  Museum  would  be  a  gigantic  task ;  but 
imagine  what  that  task  would  be  if  all  the  title- 
pages  and  other  external  indications  were  destroy- 
ed !  The  first  attempts  would  necessarily  be  of  a 
rough  approximative  kind,  merely  endeavoring  to 
make  a  sort  of  provisional  order  amid  the  chaos, 
after  which  succeeding  labors  might  introduce  bet- 
ter and  better  arrangements.  The  books  might  first 
be  grouped  according  to  size ;  but,  having  got  them 
together,  it  would  soon  be  discovered  that  size  was 
no  indication  of  their  contents :  quarto  poems  and 
duodecimo  histories,  octavo  grammars  and  folio 
dictionaries,  would  immediately  give  warning  that 
some  other  arrangement  was  needed.  Nor  would 
it  be  better  to  separate  the  books  according  to  the 
languages  in  which  they  were  written.  The  pres- 


88  STUDIO   IN   ANIMAL   LIFE. 

ence  or  absence  of  "  illustrations"  would  furnish  no 
better  guide,  while  the  bindings  would  soon  be 
found  to  follow  no  rule.  Indeed,  one  by  one,  all 
the  external  characters  would  prove  unsatisfactory, 
and  the  laborers  would  finally  have  to  decide  upon 
some  internal  characters.  Having  read  enough  of 
each  book  to  ascertain  whether  it  was  poetry  or 
prose — and,  if  poetry,  whether  dramatic,  epic,  lyric, 
or  satiric;  and  if  prose,  whether  history,  philoso- 
phy, theology,  philology,  science,  fiction,  or  essay — 
a  rough  classification  could  be  made ;  but  even  then 
there  would  be  many  difficulties,  such  as  where  to 
place  a  work  on  the  philosophy  of  history — or  the 
history  of  science — or  theology  under  the  guise  of 
science — or  essays  on  very  different  subjects,  while 
some  works  would  defy  classification. 

Gigantic  as  this  labor  would  be,  it  would  be  tri- 
fling compared  with  the  labor  of  classifying  all  the 
animals  now  living  (not  to  mention  extinct  species), 
so  that  the  place  of  any  one  might  be  securely  and 
rapidly  determined ;  yet  the  persistent  zeal  and  sa- 
gacity of  zoologists  have  done  for  the  animal  king- 
dom what  has  not  yet  been  done  for  the  library  of 
the  Museum,  although  the  titles  of  the  books  are 
not  absent.  It  has  been  done  by  patient  reading  of 
the  contents — by  anatomical  investigation  of  the  in- 
ternal structure  of  animals.  Except  on  a  basis  of 
comparative  anatomy,  there  could  have  been  no 
better  a  classification  of  animals  than  a  classification 
of  books  according  to  size,  language,  binding,  etc. 


STUDIES   IN  ANIMAL   LIFE.  89 

An  unscientific  Pliny  might  group  animals  accord- 
ing to  their  habitat;  but  when  it  was  known  that 
whales,  though  living  in  the  water  and  swimming 
like  fishes,  were  in  reality  constructed  like  air- 
breathing  quadrupeds— when  it  was  known  that 
animals  differing  so  widely  as  bees,  birds,  bats,  and 
flying  squirrels,  or  as  otters,  seals,  and  cuttlefish, 
lived  together  in  the  same  element,  it  became  ob- 
vious that  such  a  principle  of  arrangement  could 
lead  to  no  practical  result.  Nor  would  it  suffice  to 
class  animals  according  to  their  modes  of  feeding, 
since  in  all  classes  there  are  samples  of  each  mode. 
Equally  unsatisfactory  would  be  external  form — 
the  seal  and  the  whale  resembling  fishes,  the  worm 
resembling  the  eel,  and  the  eel  the  serpent. 

Two  things  were  necessary :  first,  that  the  struc- 
ture of  various  animals  should  be  minutely  studied 
and  described — which  is  equivalent  to  reading  the 
books  to  be  classified ;  and,  secondly,  that  some  ar- 
tificial method  should  be  devised  of  so  arranging  the 
immense  mass  of  details  as  to  enable  them  to  be  re- 
membered, and  also  to  enable  fresh  discoveries  readi- 
ly to  find  a  place  in  the  system.  We  may  be  per- 
fectly familiar  with  the  contents  of  a  book,  yet 
wholly  at  a  loss  where  to  place  it.  If  we  have  to 
catalogue  Hegel's  Philosophy  of  History,  for  exam- 
ple, it  becomes  a  difficult  question  whether  to  place 
it  under  the  rubric  of  philosophy,  or  under  that  of 
history.  To  decide  this  point,  we  must  have  some 
system  of  classification. 


90  STUDIES   IN   ANIMAL   LIFE. 

In  the  attempts  to  construct  a  system,  naturalists 
are  commonly  said  to  have  followed  two  methods, 
the  artificial  and  the  natural.  The  artificial  method 
seizes  some  one  prominent  characteristic,  and  groups 
all  the  individuals  together  which  agree  in  this  one 
respect.  In  Botany  the  artificial  method  classes 
plants  according  to  the  organs  of  reproduction ;  but 
this  has  been  found  so  very  imperfect  that  it  has 
been  abandoned,  and  the  natural  method  has  been 
substituted,  according  to  which  the  whole  structure 
of  the  plant  determines  its  place.  If  flying  were 
taken  as  the  artificial  basis  for  the  grouping  of  some 
animals,  we  should  find  insects  and  birds,  bats  and 
flying  squirrels  grouped  together;  but  the  natural 
method,  taking  into  consideration  not  one  character, 
but  all  the  essential  characters,  finds  that  insects, 
birds,  and  bats  differ  profoundly  in  their  organiza- 
tion :  the  insect  has  wings,  but  its  wings  are  not 
formed  like  those  of  the  bird,  nor  are  those  of  the 
bird  formed  like  those  of  the  bat.  The  insect  does 
not  breathe  by  lungs,  like  the  bird  and  the  bat ;  it 
has  no  internal  skeleton,  like  the  bird  and  the  bat ; 
and  the  bird,  although  it  has  many  points  in  com- 
mon with  the  bat,  does  not,  like  it,  suckle  its  young; 
and  thus  we  may  run  over  the  characters  of  each 
organization,  and  find  that  the  three  animals  belong 
to  widely  different  groups. 

It  is  to  Linnaeus  that  we  are  indebted  for  the 
most  ingenious  and  comprehensive  of  the  many 
schemes  invented  for  the  cataloguing  of  animal 


STUDIES   IN   ANIMAL    LIFE.  91 

forms,  and  modern  attempts  at  classification  are 
only  improvements  on  the  plan  he  laid  down.  First 
we  may  notice  his  admirable  invention  of  the  double 
names.  It  had  been  the  custom  to  designate  plants 
and  animals  according  to  some  name  common  to  a 
large  group,  to  which  was  added  a  description  more 
or  less  characteristic.  An  idea  may  be  formed  of 
the  necessity  of  a  reform  by  conceiving  what  a  la- 
borious and  uncertain  task  it  would  be  if  our  friends 
spoke  to  us  of  having  seen  a  dog  in  the  garden,  and 
on  our  asking  what  kind  of  a  dog,  instead  of  their 
saying  "  a  terrier,  a  bull-terrier,  or  a  Skye-terrier," 
they  were  to  attempt  a  description  of  the  dog. 
Something  of  this  kind  was  the  labor  of  under- 
standing the  nature  of  an  animal  from  the  vague 
description  of  it  given  by  naturalists.  Linnaeus 
rebaptized  the  whole  animal  kingdom  upon  one 
intelligible  principle.  He  continued  to  employ  the 
name  common  to  each  group,  such  as  that  of  Felis 
for  the  cats,  which  became  the  generic  name ;  and 
in  lieu  of  the  description  which  was  given  of  each 
different  kind  to  indicate  that  it  was  a  lion,  a  tiger, 
a  leopard,  or  a  domestic  cat,  he  affixed  a  specific 
name :  thus  the  animal  bearing  the  description  of  a 
lion  became  Felis  leo  ;  the  tiger,  Felis  tigris ;  the 
leopard,  Felis  leopardus ;  and  our  domestic  friend, 
Felis  catus.  These  double  names,  as  Yogt  remarks, 
are  like  the  Christian-  and  sur-names  by  which  we 
distinguish  the  various  members  of  one  family ;  and 
instead  of  speaking  of  Tomkinson  with  the  flabby 


92  STUDIES   IN   ANIMAL    LIFE. 

face  and  Tomkinson  with  the  square  forehead,  we 
simply  say  John  and  William  Tomkinson. 

Linnaeus  did  more  than  this.  He  not  only  fixed 
definite  conceptions  of  species  and  genera,  but  in- 
troduced those  of  orders  and  classes.  Cuvier  added 
families  to  genera,  and  sub-kingdoms  (embranclie- 
menis)  to  classes.  Thus  a  scheme  was  elaborated 
by  which  the  whole  animal  kingdom  was  arranged 
in  subordinate  groups :  the  sub-kingdoms  were  di- 
vided into  classes,  the  classes  into  orders,  the  orders 
into  families,  the  families  into  genera,  the  genera 
into  species,  and  the  species  into  varieties.  The 
guiding  principle  of  anatomical  resemblance  determ- 
ined each  of  these  divisions.  Those  largest  groups, 
which  resemble  each  other  only  in  having  what  is 
called  the  typical  character  in  common,  are  brought 
together  under  the  first  head.  Thus  all  the  groups 
which  agree  in  possessing  a  backbone  and  internal 
skeleton,  although  they  differ  widely  in  form,  struc- 
ture, and  habitat,  do  nevertheless  resemble  each 
other  more  than  they  resemble  the  groups  which 
have  no  backbone.  This  great  division  having  been 
formed,  it  is  seen  to  arrange  itself  in  very  obvious 
minor  divisions  or  classes — the  mammalia,  birds, 
reptiles,  and  fishes.  All  mammals  resemble  each 
other  more  than  they  resemble  birds ;  all  reptiles 
resemble  each  other  more  than  they  resemble  fishes 
(in  spite  of  the  superficial  resemblance  between  ser- 
pents and  eels  or  lampreys).  Each  class,  again, 
falls  into  the  minor  groups  of  orders,  and  on  the 


STUDIES  IN  ANIMAL   LIFE.  93 

same  principles — the  monkeys  being  obviously  dis- 
tinguished from  rodents,  and  the  carnivora  from 
the  ruminating  animals ;  and  so  of  the  rest.  In  each 
order  there  are  generally  families,  and  the  families 
fall  into  genera,  which  differ  from  each  other  only 
in  fewer  and  less  important  characters.  The  genera 
include  groups  which  have  still  fewer  differences, 
and  are  called  species;  and  these,  again,  include 
groups  which  have  only  minute  and  unimportant 
differences  of  color,  size,  and  the  like,  and  are  call- 
ed sub-species,  or  varieties. 

"Whoever  looks  at  the  immensity  of  the  animal 
kingdom,  and  observes  how  intelligibly  and  system- 
atically it  is  arranged  in  these  various  divisions, 
will  admit  that,  however  imperfect,  the  scheme  is  a 
magnificent  product  of  human  ingenuity  and  labor. 
It  is  not  an  arbitrary  arrangement,  like  the  group- 
ing of  the  stars  in  constellations;  it  expresses, 
though  obscurely,  the  real  order  of  Nature.  All 
true  classification  should  be  to  forms  what  laws  are 
to  phenomena;  the  one  reducing  varieties  to  sys- 
tematic order,  as  the  other  reduces  phenomena  to 
their  relation  of  sequence.  Now  if  it  be  true  that 
the  classification  expresses  the  real  order  of  Nature, 
and  not  simply  the  order  which  we  may  find  con- 
venient, there  will  be  something  more  than  mere 
resemblance  indicated  in  the  various  groups;  or, 
rather  let  me  say,  this  resemblance  itself  is  the  con- 
sequence of  some  community  in  the  things  com- 
pared, and  will  therefore  be  the  mark  of  some  deep- 


94  STUDIES   IN   ANIMAL   LIFE. 

er  cause.  What  is  this  cause  ?  Mr.  Darwin  holds 
that  "propinquity  of  descent  —  the  only  known 
cause  of  the  similarity  of  organic  beings — is  the 
bond,  hidden  as  it  is  by  various  degrees  of  modifi- 
cation, which  is  partially  revealed  to  us  by  our 
classifications"* — "  that  the  characters  which  natu- 
ralists consider  as  showing  true  affinity  between 
any  two  or  more  species  are  those  which  have  been 
inherited  from  a  common  parent,  and  in  so  far  all 
true  classification  is  genealogical;  that  community 
of  descent  is  the  hidden  bond  which  naturalists 
have  been  unconsciously  seeking,  and  not  pome 
unknown  plan  of  creation,  or  the  enunciation  of 
general  propositions,  and  the  mere  putting  together 
and  separating  objects  more  or  less  alike."f 

Before  proceeding  to  open  the  philosophical  dis- 
cussion which  inevitably  arises  on  the  mention  of 
Mr.  Darwin's  book,  I  will  here  set  down  the  chief 
groups,  according  to  Cuvier's  classification,  for  the 
benefit  of  the  tyro  in  natural  history,  who  will  easi- 
ly remember  them,  and  will  find  the  knowledge 
constantly  invoked. 

There  are  four  sub-kingdoms,  or  branches :  1. 
Vertebrata;  2.  Mollusca;  3.  Articulata;  4.  Eadi- 
ata. 

The  YERTEBKATA  consist  of  four  classes :  Mam- 
malia, Birds,  Eeptiles,  and  Fishes. 

The  MOLLUSCA  consist  of  six  classes :  Cephalo- 
poda (cuttlefish),  Pteropoda,  Gasteropoda  (snails, 

*  DARWIN  :   Origin  of  Species,  p.  414.  f  Ibid.,  p.  420. 


STUDIES   IN   ANIMAL   LIFE.  95 

etc.),  Acephala  (oysters,  etc.),  Brachiopoda,  and  Cir- 
rhopoda  (barnacles). — N.B.  This  last  class  is  now 
removed  from  the  Mollusks  and  placed  among  the 
Crustaceans. 

The  ARTICULATA  are  composed  of  four  classes : 
Annelids  (worms),  Crustacea  (lobsters,  crabs,  etc.), 
Arachnida  (spiders),  and  Insecta. 

The  KADLATA  embrace  all  the  remaining  forms; 
but  this  group  has  been  so  altered  since  Cuvier's 
time  that  I  will  not  burden  your  memory  just  now 
with  an  enumeration  of  the  details. 

The  reader  is  now  in  a  condition  to  appreciate 
the  general  line  of  argument  adopted  in  the  discus- 
sion of  Mr.  Darwin's  book,  which  is  at  present  ex- 
citing very  great  attention,  and  which  will,  at  any 
rate,  aid  in  general  culture  by  opening  to  many 
minds  new  tracts  of  thought.  The  benefit  in  this 
direction  is,  however,  considerably  lessened  by  the 
extreme  vagueness  which  is  commonly  attached  to 
the  word  "  species,"  as  well  as  by  the  great  want  of 
philosophic  culture  which  impoverishes  the  major- 
ity of  our  naturalists.  I  have  heard  or  read  few 
arguments  on  this  subject  which  have  not  impress- 
ed me  with  the  sense  that  the  disputants  really  at- 
tached no  distinct  ideas  to  many  of  the  phrases  they 
were  uttering.  Yet  it  is  obvious  that  we  must  first 
settle  what  are  the  facts  grouped  together  and  indi- 
cated by  the  word  "  species,"  before  we  can  carry 
on  any  discussion  as  to  the  origin  of  species.  To 
be  battling  about  the  fixity  or  variability  of  species, 


96  STUDIES   IN   ANIMAL   LIFE. 

without  having  rigorously  settled  what  species  is, 

can  lead  to  no  edifying  result. 

It  is  notorious  that  if  you  ask  even  a  zoologist, 

What  is  a  species?  you  will  always  find  that  he 
has  only  a  very  vague  answer  to  give ;  and  if  his 
answer  be  precise,  it  will  be  the  precision  of  error, 
and  will  vanish  into  contradictions  directly  it  is  ex- 
amined. The  consequence  of  this  is,  that  even  the 
ablest  zoologists  are  constantly  at  variance  as  to 
specific  characters,  and  often  can  not  agree  whether 
an  animal  shall  be  considered  of  a  new  species  or 
only  a  variety.  There  could  be  no  such  disagree- 
ments if  specific  characters  were  definite — if  we 
knew  what  species  meant,  once  and  for  all.  Ask  a 
chemist,  What  is  a  salt  ?  What  an  acid  ?  and  his 
reply  will  be  definite  and  uniformly  the  same: 
what  he  says  all  chemists  will  repeat.  Not'  so  the 
zoologist.  Sometimes  he  will  class  two  animals  as 
of  different  species,  when  they  only  differ  in  color, 
in  size,  or  in  the  numbers  of  tentacles,  etc. ;  at  other 
times  he  will  class  animals  as  belonging  to  the  same 
species,  although  they  differ  in  size,  color,  shape,  in- 
stincts, habits,  etc.  The  dog,  for  example,  is  said  to 
be  one  species  with  many  varieties  or  races.  But 
contrast  the  pug-dog  with  the  greyhound,  the  span- 
iel with  the  mastiff,  the  bull-dog  with  the  Newfound- 
land, the  setter  with  the  terrier,  the  sheep-dog  with 
the  pointer;  note  the  striking  differences  in  their 
structure  and  their  instincts,  and  you  will  find  that 
they  differ  as  widely  as  some  genera  and  as  some 


STUDIES  IN  ANIMAL  LIFE.  97 

species.  If  these  varieties  inhabited  different  coun- 
tries— if  the  pug  were  peculiar  to  Australia  and  the 
mastiff  to  Spain — there  is  not  a  naturalist  but  would 
class  them  as  of  different  species.  The  same  re- 
mark applies  to  pigeons  and  ducks,  oxen  and  sheep. 
The  reason  of  this  uncertainty  is  that  the  thing 
species  does  not  exist :  the  term  expresses  an  ab- 
straction, like  virtue,  or  whiteness ;  not  a  definite 
concrete  reality,  which  can  be  separated  from  other 
things,  and  always  be  found  the  same.  Nature  pro- 
duces individuals ;  these  individuals  resemble  each 
other  in  varying  degrees ;  according  to  their  resem- 
blances we  group  them  together  as  classes,  orders, 
genera,  and  species;  but  these  terms  only  express 
the  relations  of  resemblance,  they  do  not  indicate  the 
existence  of  such  things  as  classes,  orders,  genera,  or 
species.*  There  is  a  reality  indicated  by  each  term 
— that  is  to  say,  a  real  relation ;  but  there  is  no  ob- 
jective existence  of  which  we  could  say,  This  is 
variable,  This  is  immutable.  Precisely  as  there  is 
a  real  relation  indicated  by  the  term  goodness,  but 
there  is  no  goodness  apart  from  the  virtuous  actions 
and  feelings  which  we  group  together  under  this 
term.  It  is  true  that  metaphysicians  in  past  ages 
angrily  debated  respecting  the  immutability  of  vir- 
tue, and  had  no  more  suspicion  of  their  absurdity 
than  moderns  have  who  debate  respecting  the  fixity 

*  CUVIER  says,  in  so  many  words,  that  classes,  orders,  and  gen- 
era are  abstractions,  et  rien  de  pareil  n'existe  dans  la  nature  ;  but 
species  is  not  an  abstraction  ! — See  Lettres  a  Pfaff,  p.  179. 

E 


98  STUDIES  IN  ANIMAL  LIFE. 

of  species.  Yet  no  sooner  do  we  understand  that 
species  means  a  relation  of  resemblance  between 
animals,  than  the  question  of  the  fixity  or  varia- 
bility of  species  resolves  itself  into  this :  Can  there 
be  any  variation  in  the  resemblances  of  closely  al- 
lied animals?  A  question  which  would  never  be 
asked. 

No  one  has  thought  of  raising  the  question  of 
the  fixity  of  varieties,  yet  it  is  as  legitimate  as  that 
of  the  fixity  of  species ;  and  we  might  also  argue 
for  the  fixity  of  genera,  orders,  classes,  the  fixity  of 
all  these  being  implied  in  the  very  terms ;  since  no 
sooner  does  any  departure  from  the  type  present 
itself,  than  ~by  that  it  is  excluded  from  the  category ; 
no  sooner  does  a  white  object  become  gray  or  yel- 
low, than  it  is  excluded  from  the  class  of  white  ob- 
jects. Here,  therefore,  is  a  sense  in  which  the  phrase 
"  fixity  of  species"  is  indisputable ;  but  in  this  sense 
the  phrase  has  never  been  disputed.  When  zoolo- 
gists have  maintained  that  species  are  variable,  they 
have  meant  that  animal  forms  are  variable;  and 
these  variations,  gradually  accumulating,  result  at 
last  in  such  differences  as  are  called  specific.  Al- 
though some  zoologists,  and  speculators  who  were 
not  zoologists,  have  believed  that  the  possibility  of 
variation  is  so  great  that  one  species  may  actually 
be  transmuted  into  another,  i.  e.,  that  an  ass  may  be 
developed  into  a  horse,  yet  most  thinkers  are  now 
agreed  that  such  violent  changes  are  impossible, 
and  that  every  new  form  becomes  established  only 


STUDIES  IN  ANIMAL   LIFE.  99 

through  the  long  and  gradual  accumulation  of  mi- 
nute differences  in  divergent  directions. 

It  is  clear,  from  what  has  just  been  said,  that  the 
many  angry  discussions  respecting  the  fixity  of  spe- 
cies, which,  since  the  days  of  Lamarck,  have  dis- 
turbed the  amity  of  zoologists  and  speculative  phi- 
losophers, would  have  been  considerably  abbrevia- 
ted-had men  distinctly  appreciated  the  equivoque 
which  rendered  their  arguments  hazy.  I  am  far 
from  implying  that  the  battle  was  purely  a  verbal 
one.  I  believe  there  was  a  real  and  important  dis- 
tinction in  the  doctrines  of  the  two  camps ;  but  it 
seems  to  me  that,  had  a  clear  understanding  of  the 
fact  that  species  was  an  abstract  term  been  uniform- 
ly present  to  their  minds,  they  would  have  sooner 
come  to  an  agreement.  Instead  of  the  confusing 
disputes  as  to  whether  one  species  could  ever  be- 
come another  species,  the  question  would  have  been, 
Are  animal  forms  changeable?  Can  the  descend- 
ants of  animals  become  so  unlike  their  ancestors,  in 
certain  peculiarities  of  structure  or  instinct,  as  to  be 
classed  by  naturalists  as  a  different  species  ? 

ISTo  sooner  is  the  question  thus  disengaged  from 
equivoque  than  its  discussion  becomes  narrowed 
within  well-marked  limits.  That  animal  forms  are 
variable  is  disputed  by  no  zoologist.  The  only 
question  which  remains  is  this :  To  what  extent  are 
animal  forms  variable?  The  answers  given  have 
been  two :  one  school  declaring  that  the  extent  of 
variability  is  limited  to  those  trifling  characteristics 


100  STUDIES  IN  ANIMAL   LIFE. 

which  mark  the  different  varieties  of  each  species ; 
the  other  school  declaring  that  the  variability  is  in- 
definite, and  that  all  animal  forms  may  have  arisen 
from  successive  modifications  of  a  very  few  types, 
or  even  of  one  type. 

Now  I  would  call  your  attention  to  one  point  in 
this  discussion  which  ought  to  be  remembered  when 
antagonists  are  growing  angry  and  bitter  over  the 
subject;  it  is,  that  both  these  opinions  are  necessa- 
rily hypothetical — there  can  be  nothing  like  posi- 
tive proof  adduced  on  either  side.  The  utmost  that 
either  hypothesis  can  claim  is  that  it  is  more  con- 
sistent with  general  analogies,  and  better  serves  to 
bring  our  knowledge  of  various  points  into  har- 
mony. Neither  of  them  can  claim  to  be  a  truth 
which  warrants  dogmatic  decision. 

Of  these  two  hypotheses,  the  first  has  the  weight 
and  majority  of  authoritative  adherents.  It  de- 
clares that  all  the  different  kinds  of  bats,  for  exam- 
ple, were  distinct  and  independent  creations,  each 
species  being  originally  what  we  see  it  to  be  now, 
and  what  it  will  continue  to  be  as  long  as  it  ex- 
ists :  lions,  panthers,  pumas,  leopards,  tigers,  jagu- 
ars, ocelots,  and  domestic  cats  being  so  many  origi- 
nal stocks,  and  not  so  many  divergent  forms  of  one  orig- 
inal stock.  The  second  hypothesis  declares  that  all 
these  kinds  of  cats  represent  divergencies  of  the 
original  stock,  precisely  as  the  varieties  of  each  kind 
represent  the  divergencies  of  each  species.  It  is 
true  that  each  species,  when  once  formed,  only  ad- 


STUDIES  IN  ANIMAL  LIFE.  101 

mits  of  limited  variations ;  any  cause  which  should 
push  the  variation  beyond  certain  limits  would  de- 
stroy the  species,  because  by  species  is  meant  the 
group  of  animals  contained  within  those  limits.  Let 
us  suppose  the  original  stock  from  which  all  these 
kinds  of  cats  have  sprung  to  have  become  modified 
into  lions,  leopards,  and  tigers — in  other  words,  that 
the  gradual  accumulation  of  divergencies  has  re- 
sulted in  the  whole  family  of  cats  existing  under 
these  three  forms.  The  lions  will  form  a  distinct 
species;  this  species  varies,  and  in  the  course  of 
long  variation  a  new  species,  the  puma,  rises  by  the 
side  of  it.  The  leopards  also  vary,  and  let  us  sup- 
pose their  variation  at  length  assumes  so  marked  a 
form — in  the  ocelot — that  we  class  it  as  a  new  spe- 
cies. There  is  nothing  in  this  hypothesis  but  what 
is  strictly  consonant  with  analogies;  it  is  only  ex- 
tending to  species  what  we  know  to  be  the  fact 
with  respect  to  varieties ;  and  these  varieties  which 
we  know  to  have  been  produced  from"  one  and  the 
same  species  are  often  more  widely  separated  from 
each  other  than  the  lion  is  from  the  puma,  or  the 
leopard  from  the  ocelot.  Mr.  Darwin  remarks  that 
"  at  least  a  score  of  pigeons  might  be  chosen,  which, 
if  shown  to  an  ornithologist,  and  he  were  told  that 
they  were  wild  birds,  would  certainly,  I  think,  be 
ranked  by  him  as  well-defined  species.  Moreover, 
I  do  not  believe  that  any  ornithologist  would  place 
the  English  carrier,  the  short-faced  tumbler,  the 
runt,  the  barb,  the  pouter,  and  fantail  in  the  same 


102  STUDIES  IN  ANIMAL  LIFE. 

genus,  more  especially  as  in  each,  of  these  breeds 
several  truly -inherited  sub-breeds  or  species,  as  he 
might  have  called  them,  could  be  shown  him." 

The  development  of  numerous  specific  forms, 
widely  distinguished  from  each  other,  out  of  one 
common  stock,  is  not  a  whit  more  improbable  than 
the  development  of  numerous  distinct  languages 
out  of  a  common  parent  language,  which  modern 
philologists  have  proved  to  be  indubitably  the  case. 
Indeed,  there  is  a  very  remarkable  analogy  between 
philology  and  zoology  in  this  respect:  just  as  the 
comparative  anatomist  traces  the  existence  of  simi- 
lar organs,  and  similar  connections  of  these  organs, 
throughout  the  various  animals  classed  under  one 
type,  so  does  the  comparative  philologist  detect  the 
family  likeness  in  the  various  languages  scattered 
from  China  to  the  Basque  Provinces,  and  from  Cape 
Comorin  across  the  Caucasus  to  Lapland — a  like- 
ness which  assures  him  that  the  Teutonic,  Celtic, 
Wendic,  Italic,  Hellenic,  Iranic,  and  Indie  languages 
are  of  common  origin,  and  separated  from  the  Ara- 
bian, Aramean,  and  Hebrew  languages,  which  have 
another  origin.  Let  us  bring  together  a  French- 
man, a  Spaniard,  an  Italian,  a  Portuguese,  a  Walla- 
chian,  and  a  Khastian,  and  we  shall  hear  six  very 
different  languages  spoken,  the  speakers  severally 
unintelligible  to  each  other,  their  languages  differ- 
ing so  widely  that  one  can  not  be  regarded  as  the 
modification  of  the  other ;  yet  we  know  most  posi- 
tively that  all  these  languages  are  offshoots  from 


STUDIES  IN  ANIMAL 

the  Latin,  which  was  once  a  living  language,  but 
which  is  now,  so  to  speak,  a  fossil.  The  various 
species  of  cats  do  not  differ  more  than  these  six 
languages  differ,  and  yet  the  resemblances  point  in 
each  case  to  a  common  origin.  Max  Muller,  in  his 
brilliant  essay  on  Comparative  Mythology* has  said, 
"  If  we  knew  nothing  of  the  existence  of  Latin — 
if  all  historical  documents  previous  to  the  fifteenth 
century  had  been  lost — if  tradition,  even,  was  silent 
as  to  the  former  existence  of  a  Eoman  empire,  a 
mere  comparison  of  the  six  Eoman  dialects  would 
enable  us  to  say  that  at  some  time  there  must  have 
been  a  language  from  which  all  these  modern  dia- 
lects derived  their  origin  in  common ;  for  without 
this  supposition  it  would  be  impossible  to  account 
for  the  facts  exhibited  by  these  dialects.  Let  us 
look  at  the  auxiliary  verb.  "We  find : 

Italian.    Wallachian.     Rhsetian.      Spanish.  Portuguese.      French. 
I  am sono      sum  sunt    sunt  soy          sou          suis. 

Thou  art sei  es  eis  erea  es  es. 

He  is e  <§  (este)  ei  es  he  est. 

We  are siamo  suntemu  essen  somos  somos  sommes. 

You  are siete  suntefi  esses  sois  sois  etes  (estes). 

They  are sono  sunt  eon  (sun)  son  eao  sent. 

It  is  clear,  even  from  a  short  consideration  of  these 
forms,  first,  that  all  are  but  varieties  of  one  common 
type ;  secondly,  that  it  is  impossible  to  consider  any 
one  of  these  six  paradigms  as  the  original  from 
which  the  others  had  been  borrowed.  To  this  we 
may  add,  thirdly,  that  in  none  of  the  languages  to 
which  these  verbal  forms  belong  do  we  find  the 

*  See  Oxford  Essays,  1856. 


104  STUDIES  IN   ANIMAL  LIFE. 

elements  of  which  they  could  have  been  composed. 
If  we  find  such  forms  as  f  ai  aime,  we  can  explain 
them  by  a  mere  reference  to  the  radical  means  which 
French  has  still  at  its  command,  and  the  same  may 
be  said  even  of  compounds  like  f  aimer  ai,  i.  e.,  je- 
aimer-ai,  I  have  to  love,  I  shall  love.  But  a  change 
from  je  suis  to  tu  es  is  inexplicable  by  the  light  of 
French  grammar.  These  forms  could  not  have 
grown,  so  to  speak,  on  French  soil,  but  must  have 
been  handed  down  as  relics  from  a  former  period — 
must  have  existed  in  some  language  antecedent  to 
any  of  the  Eoman  dialects.  Now,  fortunately,  in 
this  case,  we  are  not  left  to  a  mere  inference,  but  as 
we  possess  the  Latin  verb,  we  can  prove  how,  by 
phonetic  corruption  and  by  mistaken  analogies, 
every  one  of  the  six  paradigms  is  but  a  national 
metamorphosis  of  the  Latin  original. 

"Let  us  now  look  at  another  set  of  paradigms : 

Sanscrit.  j£|j£  Zend.  Doric.  sla°Uic>  Latin.  Gothic.  Armen. 

I  am asmi  esmi  ahmi  enm  yesmo  sum  im  em. 

Thou  art asi  essi  ahi  e<ro-i  yesi  ea  is  es. 

He  is asti  esti  asti  ka-ri  yesto  est  ist  e. 

We  (two)  are . .  'svas  esva  yesva  . . .  eiju 

You  (two)  are. .  'sthas  esta  stho?  eo-rov  yesta  ...  sijuts  ... 

They  (two)  are.  'stas  (esti)  sto?  ea-rov  yesta  

We  are 'smas  esmi  hmahi  eoyxer  yesmo  sumus  sijum  emq. 

You  are 'stha  este  stha  eo-re  yeste  estis  sijup  eq. 

They  are santi  (esti)  h^nti  ev-ri  somtS  sunt  sind  en. 

"  From  a  careful  consideration  of  these  forms,  we 
ought  to  draw  exactly  the  same  conclusions ;  first- 
ly, that  all  are  but  varieties  of  one  common  type ; 
secondly,  that  it  is  impossible  to  consider  any  of 
them  as  the  original  from  which  the  others  have 


STUDIES  IN  ANIMAL   LIFE.  105 

been  borrowed ;  and,  thirdly,  that  here  again  none 
of  the  languages  in  which  these  verbal  forms  occur 
possess  the  elements  of  which  they  are  composed." 

All  these  languages  resemble  each  other  so  close- 
ly that  they  point  to  some  more  ancient  language 
which  was  to  them  what  Latin  was  to  the  six  Ko- 
man  languages ;  and  in  the  same  way  we  are  justi- 
fied in  supposing  that  all  the  classes  of  the  verte- 
brate animals  point  to  the  existence  of  some  elder 
type,  now  extinct,  from  which  they  were  all  de- 
veloped. 

I  have  thus  stated  what  are  the  two  hypotheses 
on  this  question.  There  is  only  one  more  prelimi- 
nary which  it  is  needful  to  notice  here,  and  that  is, 
to  caution  the  reader  against  the  tendency,  unhap- 
pily too  common,  of  supposing  that  an  adversary 
holds  opinions  which  are  transparently  absurd. 
When  we  hear  a  hypothesis  which  is  either  novel 
or  unacceptable  to  us,  we  are  apt  to  draw  some  very 
ridiculous  conclusion  from  it,  and  to  assume  that 
this  conclusion  is  seriously  held  by  its  upholders. 
Thus  the  zoologists  who  maintain  the  variability 
of  species  are  sometimes  asked  if  they  believe  a 
goose  was  developed  out  of  an  oyster,  or  a  rhinoce- 
ros from  a  mouse  ?  the  questioner  apparently  having 
no  misgiving  as  to  the  candor  of  his  ridicule.  There 
are  three  modes  of  combating  a  doctrine.  The  first 
is  to  point  out  its  strongest  positions,  and  then 
show  them  to  be  erroneous  or  incomplete ;  but  this 
plan  is  generally  difficult,  and  sometimes  impossi- 
E2 


106  STUDIES  IN  ANIMAL  LIFE. 

ble ;  it  is  not,  therefore,  much  in  vogue.  The  sec- 
ond is  to  render  the  doctrine  ridiculous  by  pretend- 
ing that  it  includes  certain  extravagant  propositions 
of  which  it  is  entirely  innocent.  The  third  is  to 
render  the  doctrine  odious  by  forcing  on  it  certain 
conclusions  which  it  would  repudiate,  but  which  are 
declared  to  be  "  the  inevitable  consequences"  of  such 
a  doctrine.  JSTow  it  is  undoubtedly  true  that  men 
frequently  maintain  very  absurd  opinions;  but  it 
is  neither  candid  nor  wise  to  assume  that  men  who 
otherwise  are  certainly  not  fools,  hold  opinions  the 
absurdity  of  which  is  transparent. 

Let  us  not,  therefore,  tax  the  followers  of  La- 
marck, Greoffroy  St.  Hilaire,  or  Mr.  Darwin  with  ab- 
surdities they  have  not  advocated,  but  rather  en- 
deavor to  see  what  solid  argument  they  have  for 
the  basis  of  their  hypothesis. 


STUDIES  IN  ANIMAL  LIFE.  107 


CHAPTER  Y. 

Talking  in  Beetles. — Identity  of  Egyptian  Animals  with  those  now 
existing :  Does  this  prove  Fixity  of  Species  ? — Examination  of 
the  celebrated  Argument  of  Species  not  having  altered  in  four 
thousand  Years. — Impossibility  of  distinguishing  Species  from 
Varieties. — The  Affinities  of  Animals. — New  Facts  proving  the 
Fertility  of  Hybrids. — The  Hare  and  the  Rabbit  contrasted. — 
Doubts  respecting  the  Development  Hypothesis. — On  Hypoth- 
esis in  Natural  History. — Pliny,  and  his  Notion  on  the  Forma- 
tion of  Pearls. — Are  Pearls  owing  to  a  Disease  of  the  Oyster  ? — 
Formation  of  the  Shell;  Origin  of  Pearls. — How  the  Chinese 
manufacture  Pearls.  * 

A  WITTY  friend  of  mine  expressed  her  sense  of 
the  remoteness  of  the  ancient  Egyptians,  and  her 
difficulty  in  sympathizing  with  them,  by  declar- 
ing that  "  they  talked  in  beetles,  you  know.'1'1  She 
referred,  of  course,  to  the  hieroglyphics  in  which 
that  curious  people  now  speak  to  us  from  ancient 
tombs.  Whether  these  swarthy  sages  were  elo- 
quent and  wise,  or  obscure  and  otherwise,  in  their 
beetle-speech,  it  is  certain  that  entomologists  of  our 
day  recognize  their  beetles  as  belonging  to  the  same 
species  that  are  now  gathered  into  collections.  Such 
as  the  Egyptians  knew  them,  such  we  know  them 
now.  Nay,  the  sacred  cats  found  in  those  ancient 
tombs  are  cats  of  the  same  kind  as  our  own  familiar 
mousers ;  they  purred  before  Pharaoh  as  they  purr 


108  STUDIES  IN  ANIMAL  LIFE. 

on  our  hearth-rugs;  and  the  descendants  of  the 
very  dogs  which  irreligiously  worried  those  cats 
are  to  this  day  worrying  the  descendants  of  those 
sacred  cats.  The  grains  of  wheat  which  the  savans 
found  in  the  tombs  were  planted  in  the  soil  of 
France,  and  grew  into  waving  corn  in  no  respect 
distinguishable  from  the  corn  grown  from  the  grain 
of  the  previous  year. 

Have  these  familiar  facts  any  important  signifi- 
cance? Are  we  entitled  to  draw  any  conclusion 
from  the  testimony  of  paintings  and  sculptures,  at 
least  four  thousand  years  old,  which  show  that  sev- 
eral of  our  well-known  species  of  animals,  and  sev- 
eral of  the  well-marked  races  of  men,  existed  then, 
and  have  not  changetfsince  then  ?  Nimrod  hunted 
with  dogs  and  horses,  which  would  be  claimed  as 
ancestors  by  the  dogs  and  horses  at  Melton  Mow- 
bray.  The  negroes  who  attended  Semiramis  and 
Khamses  are  in  every  respect  similar  to  the  negroes 
now  toiling  amid  the  sugar-canes  of  Alabama.  If, 
during  four  thousand  years,  species  and  races  have 
not  changed,  why  should  we  suppose  that  they  ever 
will  change  ?  Why  should  we  not  take  our  stand 
on  that  testimony,  and  assert  that  species  are  un- 
changeable ? 

Such  has  been  the  argument  of  Cuvier  and  his 
followers;  an  argument  on  which  they  have  laid 
great  stress,  and  which  they  have  further  strength- 
ened by  a  challenge  to  adversaries  to  produce  one 
single  case  where  a  transmutation  of  species  has 


STUDIES  IN  ANIMAL  LIFE.  109 

taken  place:  "Here  we  show  you  evidence  that 
species  has  persisted  unaltered  during  four  thousand 
years,  and  you  can  not  show  us  a  single  case  of 
species  having  changed — you  can  not  show  us  one 
case  of  a  wolf  becoming  a  dog,  an  ass  becoming  a 
horse,  a  hare  becoming  a  rabbit.  Yet  you  must 
admit  that  if  there  were  any  inherent  tendency 
to  change,  four  thousand  years  is  a  long  enough 
period  for  that  tendency  to  display  itself  in ;  and 
we  ought  to  see  a  very  marked  difference  between 
the  species  which  lived  under  Semiramis  and  those 
which  are  living  under  Victoria.  Instead  of  this, 
we  see  that  there  has  been  no  change :  the  dog  has 
remained  a  dog,  and  the  horse  has  remained  a 
horse ;  every  species  retains  its  well-marked  char- 
acters." 

No  one  will  say  that  I  have  not  done  justice  to 
this  argument.  I  have  stated  it  as  clearly  and  for- 
cibly as  possible,  not  with  any  design  to  captivate 
your  assent,  but  to  make  the  answer  complete. 
This  argument  is  the  cheval  de  batailk  of  the  Cuvier 
school ;  but,  like  many  other  argumentative  war- 
horses,  it  proves,  on  close  inspection,  to  be  spavined 
and  broken-winded.  The  first  criticism  we  must 
pass  on  it  is  that  it  implies  the  existence  of  species 
as  a  thing  which  can  be  spoken  of  as  fixed  or  varia- 
ble ;  whereas,  as  we  saw  in  the  last  chapter,  species 
is  an  abstraction,  like  whiteness  or  strength.  No  one 
supposes  that  there  exists  any  whiteness  apart  from 
white  things,  or  strength  apart  from  strong  things ; 


110  STUDIES  IN  ANIMAL  LIFE. 

yet  the  naturalists  who  maintain  the  fixity  of  spe- 
cies constantly  talk  as  if  species  existed  independ- 
ently of  the  individual  animals.  Instead  of  saying 
that  by  the  word  species  is  indicated  a  certain  group 
of  characters,  and  that  whenever  we  meet  with  this 
group  we  say,  here  is  an  animal  of  the  same  spe- 
cies, they  explicitly  declare,  or  tacitly  imply,  that  al- 
though an  individual  dog  may  vary,  there  is  some- 
thing above  all  individuals — the  species — and  that 
can  not  vary.  As  it  is  possible  some  readers  may 
protest  that  no  respectable  authority  in  modern 
times  ever  held  the  opinion  here  imputed  to  a 
school,  I  will  quote  the  very  explicit  language  of 
one  of  Cuvier's  disciples — the  last  editor  of  Buffon 
— who,  no  later  than  1856,  could  declare  that  "  spe- 
cies are  the  primitive  forms  of  Nature.  Individu- 
als are  nothing  but  the  representatives — the  copies 
of  these  forms:  Les  espbces  sont  les  formes  primitives 
de  la  Nature.  Les  individus  n'en  sont  que  des  repre- 
sentations, des  copies."*  According  to  this  very  ex- 
plicit but  very  extravagant  statement,  an  individual 
dog  is  nothing  but  a  copy  of  the  primitive  form — 
the  typical  dog — the  idea  of  a  dog,  as  Plato  would 
say ;  and,  of  course,  if  this  be  true,  it  matters  little 
how  widely  individual  dogs  may  vary,  the  type,  or 
species,  of  which  it  is  the  representative,  remains 
unaltered.  Indeed,  it  is  on  this  ground  that  many 
physiologists  explain  the  fact  of  hereditary  trans- 
mission: the  individual  may  vary,  it  is  said,  but 

*  FLOURENS  :    Cours  de  Physioloyie  Comparee,  1856,  p.  9. 


STUDIES  IN  ASTTMAL  LIFE.  Ill 

the  species  is  preserved ;  and  if  a  dog  without  its 
fore  paws  has  offspring,  every  one  of  which  pos- 
sesses the  fore  paws,  the  reason  is,  that  Tidee  de 
Tespece  se  reproduit  dans  le  fruit,  et  lui  donne  des  or- 
ganes  qui  manquaient  au pbre  ou  d  la  mere*  It  is 
not  easy  to  understand  how  the  idea  of  a  species  can 
reproduce  itself,  and  give  the  offspring  of  a  dog  the 
organs  which  were  wanting  in  the  parents ;  but  to 
those  who  believe  that  species  exist  independently 
of  individuals,  and  form  the  only  real  existences, 
the  conception  may  be  easier. 

I  have  too  much  respect  for  the  reader  to  drag 
him  through  a  refutation  of  such  philosophy  as 
this ;  the  statement  of  the  opinion  is  enough.  And 
yet,  unless  some  such  opinion  be  maintained,  the 
doctrine  of  fixity  of  species  is  without  a  basis ;  for 
if  it  be  said  that  the  group  of  characters  which  con- 
stitute the  dog  are  incapable  of  change,  and  in  this 
sense  species  are  fixed,  we  have  to  ask  what  evi- 
dence there  can  be  for  such  an  assertion?  since  it 
is  notorious  that  individual  dogs  do  show  a  change 
in  some  of  the  characters  of  the  group.  We  shall 
be  referred  to  the  Egyptian  tombs  for  evidence. 
M.  Flourens  assures  us  that  not  only  are  these 
tombs  evidence  that  species  have  not  changed  in 
four  thousand  years,  but  that  no  species  has  changed 
— aucune  espece  n'a  change — which  is  surely  stepping 
a  long  way  beyond  the  precincts  of  the  tombs ! 

It  may  be  paradoxical,  but  it  is  strictly  true,  that 

*  BUKDACH  :  Physiologic,  ii.,  245. 


112  STUDIES  IN  ANIMAL  LIFE. 

the  fact  of  particular  species  having  remained  un- 
altered during  four  thousand  years  does  not  add 
the  slightest  weight  to  the  evidence  in  favor  of  the 
fixity  of  species.  "  What !"  some  may  exclaim,  "  do 
you  pretend  that  four  thousand  years  is  not  a  period 
long  enough  to  prove  the  fixity  of  animal  forms  ?" 
Yes ;  I  affirm  that  four  thousand,  or  forty  thousand, 
prove  no  more  than  four.  It  is  only  by  a  fallacy 
that  the  opposite  opinion  could  gain  acceptance. 
You  would  not  suppose  that  I  had  strengthened 
my  case  if,  instead  of  contenting  myself  with  stating 
reasons  once,  I  repeated  these  same  reasons  during 
forty  successive  pages ;  you  would  remind  me  that 
this  iteration  was  not  cumulation,  and  that  no  force 
was  given  to  my  fortieth  assertion  which  the  first 
wanted.  Why,  then,  do  you  ask  me  to  accept  the 
repetition  of  the  same  fact  four  thousand  times  over 
as  an  increase  of  evidence?  It  is  a  familiar  fact 
that  like  produces  like — that  dogs  resemble  dogs, 
and  do  not  resemble  buffaloes ;  this  fact  is,  of  course, 
deepened  in  our  conviction  by  the  unvarying  evi- 
dence we  see  around  us,  and  is  guaranteed  by  the 
philospphical  axiom  that  like  causes  produce  like 
effects ;  but  when  once  such  a  conception  is  formed, 
it  can  gain  no  fresh  strength  from  any  particular 
instance.  If  we  believe  that  crows  are  black,  we 
do  not  hold  that  belief  more  firmly  when  we  are 
shown  that  crows  were  black  four  thousand  years 
ago.  In  like  manner,  if  it  is  an  admitted  fact  that 
individuals  always  reproduce  individuals  closely  re- 


STUDIES  IN  ANIMAL  LIFE.  113 

sembling  themselves,  it  is  not  a  whit  more  surpris- 
ing that  the  dogs  of  Victoria  should  resemble  the 
dogs  of  Semiramis,  than  that  they  should  resemble 
their  parents :  the  chain  of  four  thousand  years  is 
made  up  of  many  links,  each  link  being  a  repetition 
of  the  other.  So  long  as  a  single  pair  of  dogs  re- 
sembling each  other  unite,  so  long  will  there  be 
specimens  of  that  species,  simply  because  the  chil- 
dren inherit  the  characteristics  of  the  parents.  So 
long  as  negroes  marry  with  negroes,  and  Jews  with 
Jews,  so  long  must  there  be  a  perpetuation  of  the 
negro  and  Jewish  types ;  but  the  tenth  generation 
adds  nothing  to  the  evidence  of  the  first,  nor  the 
ten  thousandth  to  the  tenth. 

I  believe  that  this  fallacy,  which  destroys  the 
whole  value  of  the  Cuvierian  argument,  has  not 
before  been  pointed  out ;  and  even  now  you  may 
perhaps  ask  if  the  fixity  of  species  is  not  proved  by 
the  fact  that  like  produces  like?  So  far  from  this, 
that  it  is  only  by  the  aid  of  such  a  fact  in  organic 
nature  that  we  can  imagine  new  species  to  have 
arisen ;  in  other  words,  those  who  believe  in  the 
variability  of  species,  and  the  introduction  of  new 
forms  by  means  of  modification  from  the  old,  al- 
ways invoke  the  law  of  hereditary  transmission  as 
the  means  of  establishing  accidental  variations. 
Thus,  let  us  suppose  the  Egyptian  king  to  have 
had  one  hundred  dogs,  all  of  them  staghounds,  and 
no  other  form  of  dog  to  have  existed  at  that  time 
in  that  country ;  the  dog  species  would  be  repre- 


114  STUDIES  IN  ANIMAL  LIFE. 

sented  by  the  staghound.  These  staghounds  would 
transmit  to  their  offspring  all  their  specific  charac- 
ters. But,  as  every  one  knows,  however  much  dogs 
may  resemble  each  other,  they  always  present  in- 
dividual differences  in  size,  color,  strength,  intelli- 
gence, etc.  Now,  if  any  one  of  these  differences 
should  happen  to  become  marked,  and  to  increase 
by  the  intermarriage  of  two  dogs  similarly  distin- 
guished by  the  marked  peculiarity,  this  peculiarity 
would  in  time  become  established  by  hereditary 
transmission,  and  would  form  the  starting-point  of 
a  new  race  of  dogs — say  the  greyhound— unless  it 
were  obliterated  by  intermarriage  with  dogs  of  the 
old  type.  In  the  former  case,  we  should  have  two 
races  of  dogs  among  the  descendants  of  those  fig- 
ured on  the  Egyptian  tombs;  but  as  one  of  these 
races  would  still  preserve  the  original  staghound 
type,  Cuvier  would  refer  to  it  as  a  proof  that  spe- 
cies had  not  varied.  "We,  on  the  other  hand,  should 
point  to  the  greyhound  as  proof  that  animal  forms 
are  variable,  and  that  a  new  form  had  arisen  from 
modification  of  the  old. 

An  objection  will  at  once  be  raised  to  this  illus- 
tration, to  the  effect  that  all  zoologists  admit  the 
possibility  of  new  varieties  or  races  being  formed ; 
but  they  deny  that  new  species  can  be  formed.  It 
is  here  that  the  equivoque  of  the  word  species  pre- 
vents a  clear  understanding  of  each  other's  argu- 
ment. "Whiteness  may  justly  be  said  to  be  unalter- 
able; but  white  things  may  vary — they  may  be- 


STUDIES  IN  ANIMAL  LIFE.  115 

come  gray  or  yellow.  In  like  manner  species  must 
be  invariable,  because  species  is  a  word  indicating 
a  particular  group  of  characters ;  but  animals  may 
vary  in  these  characters:  they  may  present  some 
of  the  characters  less  or  more  developed,  and  they 
may  even  want  some  of  them.  Now,  as  there  is 
no  absolute  standard  of  what  constitutes  species, 
what  sub-species,  and  what  varieties,  it  becomes 
impossible  to  say  whether  any  individual  variation 
in  an  animal  form  shall  constitute  a  new  variety  or 
a  new  species.  "With  regard  to  dogs,  the  differ- 
ences between  the  various  races  are  so  numerous 
and  so  marked  as  would  suffice  to  constitute  spe- 
cies, and  even  genera,  in  other  groups  of  animals. 

"We  must  relinquish  the  idea  of  proving  any 
thing  by  the  paintings  and  sculptures  of  the  an- 
cients. When  we  find  an  Egyptian  plow  closely 
resembling  the  plow  still  in  use  in  some  places,  we 
may  identify  it  as  of  the  same  "  species"  as  our 
own ;  but  this  does  not  disprove  the  fact  that  steam- 
plows,  and  plows  of  various  construction,  have 
been  since  invented,  all  of  them  being  modifica- 
tions of  the  original  type.  Formerly,  and  for  many 
years,  the  stage-coach  was  our  approved  mode  of 
conveyance — and  it  is  still  kept  up  in  some  dis- 
tricts ;  nevertheless,  modifications  of  coachroad  into 
tramroad,  and  tramroad  into  railroad,  have  gradu- 
ally resulted  in  a  mode  of  conveyance  utterly  un- 
like the  stage-coach.  It  is  the  same  with  animals. 

Let  us  never  forget  that  species  have  no  exist- 


116  STUDIES  IN  ANIMAL  LIFE. 

ence.  Only  individuals  exist,  and  these  all  vary 
more  or  less  from  each  other.  When  the  modifica- 
tions are  slight,  they  have  no  name ;  when  they  are 
more  marked,  and  are  transmitted  from  one  gener- 
ation to  another,  they  constitute  particular  races  or 
varieties ;  when  the  differences  are  still  more  mark- 
ed, they  constitute  sub-species ;  but,  as  Mr.  Darwin 
says,  "  Certainly  no  clear  line  of  demarkation  has 
yet  been  drawn  between  species  and  sub-species; 
that  is,  the  forms  which  in  the  opinion  of  some  nat- 
uralists come  very  near  to,  but  do  not  quite  arrive 
at  the  rank  of  species ;  or  again,  between  sub-spe- 
cies and  well-marked  varieties,  or  between  lesser 
varieties  and  individual  differences.  These  differ- 
ences blend  into  each  other  in  an  insensible  series ; 
and  a  series  impresses  the  mind  with  the  idea  of  an 
actual  passage."  But  the  same  process  of  diverg- 
ence which  establishes  varieties  out  of  individual 
differences,  and  species  out  of  varieties,  also  serves 
to  establish  genera  out  of  species,  orders  out  of  gen- 
era, and  classes  out  of  orders.  It  is  doubtless  diffi- 
cult to  conceive  by  what  process  of  modification 
two  animals  of  distinct  genera,  say  a  dog  and  a  cat, 
were  produced  from  a  common  stock ;  but  organic 
analogies  in  abundance  render  it  easy  of  belief.  If 
we  knew  as  much  of  zoology  as  we  do  of  embryol- 
ogy, in  respect  of  the  affinities  of  divergent  forms, 
it  would  be  far  less  surprising  that  two  different 
genera  should  arise  from  a  common  stock,  than  that 
all  the  various  parts  of  the  skeleton  should  arise 


STUDIES  IN  ANIMAL  LIFE.  117 

from  a  common  osseous  element.  "We  know  that 
the  jaws  are  identical  with  arms  and  legs — both  be- 
ing divergent  modifications  of  a  common  osseous 
structure.  We  know  that  the  arm  of  a  man  is 
identical  with  the  fin  of  a  whale  or  the  wing  of  a 
bird.  The  differences  here  in  form,  size,  and  func- 
tion are  much  greater  than  the  differences  which 
establish  orders  and  classes  in  the  animal  series. 
Unless  animal  forms  were  modifications  of  some 
common  type,  it  would  be  difficult  to  explain  their 
remarkable  affinities.  As  Mr.  Darwin  says,  "  It  is 
a  truly  wonderful  fact — the  wonder  of  which  we 
are  apt  to  overlook  from  familiarity — that  all  ani- 
mals and  all  plants  throughout  all  time  and  space 
should  be  related  to  each  other  in  group  subordi- 
nate to  group,  in  the  manner  which  we  every  where 
behold,  namely,  varieties  of  the  same  species  most 
closely  related  together,  species  of  the  same  genus 
less  closely  and  unequally  related  together,  forming 
sections  and  sub-genera,  species  of  distinct  genera 
much  less  closely  related,  and  genera  related  in  dif- 
ferent degrees,  forming  sub-families,  families,  orders, 
sub-classes,  and  classes.  The  several  subordinate 
groups  in  any  class  can  not  be  ranked  in  a  single 
file,  but  seem  rather  to  be  clustered  round  points, 
and  these  round  other  points,  and  so  on  in  almost 
endless  circles.  On  the  view  that  each  species  has 
been  independently  created,  I  can  see  no  explana- 
tion of  this  great  fact  in  the  classification  of  all  or- 
ganic beings ;  but,  to  the  best  of  my  judgment,  it  is 


118  STUDIES  IN  ANIMAL  LIFE. 

explained  through,  inheritance,  and  the  complex 
action  of  natural  selection  entailing  extinction  and 
divergence  of  character.  The  affinities  of  all  the 
beings  of  the  same  class  have  sometimes  been  rep- 
resented by  a  great  tree.  I  believe  this  simile 
largely  speaks  the  truth.  The  green  and  budding 
twigs  may  represent  existing  species,  and  those  pro- 
duced during  each  former  year  may  represent  the 
long  succession  of  extinct  species.  At  each  period 
of  growth  all  the  growing  twigs  have  tried  to  branch 
out  on  all  sides,  and  to  overtop  and  kill  the  sur- 
rounding twigs  and  branches,  in  the  same  manner 
as  species  and  groups  of  species  have  tried  to  over- 
master other  species  in  the  great  struggle  for  life. 
The  limbs  divided  into  great  branches,  and  these 
into  lesser  branches,  were  themselves  once,  when 
the  tree  was  small,  budding  twigs;  and  this  con- 
nection of  the  former  and  present  buds  by  ramify- 
ing branches  may  well  represent  the  classification 
of  all  extinct  and  living  species  in  groups  subordi- 
nate to  groups.  Of  the  many  twigs  which  flourish- 
ed when  the  tree  was  a  mere  bush,  only  two  or 
three,  now  grown  into  great  branches,  yet  survive 
and  bear  all  the  other  branches ;  so  with  the  spe- 
cies which  lived  during  long-past  geological  peri- 
ods, very  few  now  have  living  and  modified  de- 
scendants. ...  As  buds  give  rise  by  growth  to 
fresh  buds,  and  these,  if  vigorous,  branch  out  and 
overtop  on  all  sides  many  a  feebler  branch,  so  by 
generation,  I  believe,  it  has  been  with  the  great 


STUDIES  IN  ANIMAL  LIFE.  119 

Tree  of  Life,  which,  fills  with  its  dead  and  broken 
branches  the  crust  of  the  earth,  and  covers  the  sur- 
face with  its  ever-branching  and  beautiful  ramifica- 
tions."* 

It  will  not  be  expected  that  in  these  brief  and 
desultory  remarks  I  should  touch  on  all,  or  nearly 
all,  the  important  points  in  the  discussion  respect- 
ing the  fixity  of  species.  Mr.  Darwin's  book  is  in 
every  body's  hands,  and  my  object  has  been  to  fa- 
cilitate, if  possible,  the  comprehension  of  his  book, 
and  the  adoption  of  a  more  philosophical  hypothe- 
sis, by  pointing  out  the  weakness  of  the  chief  argu- 
ment on  the  other  side.  There  is  one  more  argu- 
ment which  may  be  noticed — the  more  so  as  it  is 
constantly  adduced  with  triumph  by  the  one  school, 
and  admitted  as  a  difficulty  by  the  other.  Its  force 
is  so  great  that  it  prevents  many  from  accepting 
the  development  hypothesis.  It  is  the  argument 
founded  on  the  alleged  impossibility  of  hybrids 
continuing  the  race.  More  than  two  or  three  gen- 
erations of  hybrids,  it  is  said,  can  never  be  main- 
tained; after  that,  the  new  form  perishes,  thus 
clearly  showing  how  Nature  repudiates  such  amal- 
gamations, and  keeps  her  species  jealously  distinct 
and  invariable.  This  argument  is  held  to  be  the 
touchstone  of  the  doctrine  of  species.  I  wish  it 
were  so ;  because,  in  that  case,  the  question  would 
no  longer  be  one  of  hypothesis,  since  we  have  now 
the  indubitable  proof  that  some  hybrids  are  fertile 
unto  the  thirteenth  generation  and  onward. 

*  DARWIN  :  Origin  of  Species,  p.  128. 


120  STUDIES  IN  ANIMAL  LIFE. 

A  history  of  the  various  attempts  which  have 
been  made  to  prove  and  disprove  the  fertility  of 
hybrids  would  lead  us  beyond  our  limits ;  the  curi- 
ous reader  is  referred  to  the  works  cited  below.* 
One  decisive  case  alone  shall  be  given  here,  and  no 
one  will  dispute  that  it  is  decisive. 

The  hare  (lepus  timidus)  is  assuredly  of  a  distinct 
species  from  the  rabbit  (lepus  cuniculus).  So  dis- 
tinct are  these  species,  that  any  classification  which 
should  range  them  as  one  would  violate  every  ac- 
cepted principle.  The  hare  is  solitary,  the  rabbit 
gregarious;  the  hare  lives  on  the  surface  of  the 
earth,  the  rabbit  burrows  under  the  surface ;  the 
hare  makes  her  home  among  the  bushes,  the  rabbit 
makes  a  sort  of  nest  for  her  young  in  her  burrow— 
keeping  them  there  till  they  are  weaned ;  the  hare 
has  reddish-brown  flesh,  the  rabbit  white  flesh ; 
while  the  odor  exhaled  by  each,  and  the  flavor  of 
each,  are  unmistakably  different.  The  hare  has 
many  anatomical  characters  differing  from  those  of 
the  rabbit,  such  as  greater  length  and  strength  of 
the  hind  legs,  larger  body,  shorter  intestine,  thicker 
skin,  firmer  hair,  and  different  color.  The  hare 
breeds  only  twice  or  thrice  a  year,  and  at  each  lit- 
ter has  only  two  or  four;  the  rabbit  will  breed 
eight  times  a  year,  and  each  time  has  four,  six, 
seven,  and  even  eight  young  ones.  Finally,  the 

*  ISIDORE  GEOFFROY  ST.  HILAIRE  :  Hist.  Nat.  Generate  des 
Regnes  Organiques,  1860,  iii.,  207  sq.  BROCA  :  Memoire  sur  IHy- 
bridite,  in  BROWN-SEQUARD'S  Journal  de  la  Physiologic,  1859. 


STUDIES  IN  ANIMAL  ^«,  „,   ,    fir  „»_ 

SITY 

two  are  violent  foes:  the  rabbits  always  destroy 
the  hares,  and  all  sportsmen  are  aware  that  if  the 
rabbits  be  suffered  to  multiply  on  an  estate,  there 
will  be  small  chance  of  hares. 

Nevertheless,  between  species  so  distinct  as  these, 
a  new  hybrid  race  has  been  reared  by  M.  Eouy,  of 
Angouleme,  who  each  year  sends  to  market  upward 
of  a  thousand  of  his  Leporides,  as  he  calls  them. 
His  object  was  primarily  commercial,  not  scientific. 
His  experiments,  extending  from  1847  to  the  pres- 
ent time,  have  not  only  been  of  great  commercial 
value — introducing  a  new  and  valuable  breed — 
but  have  excited  the  attention  of  scientific  men, 
who  are  now  availing  themselves  of  his  skill  and  ex- 
perience to  help  them  in  the  solution  of  minor  prob- 
lems. It  is  enough  to  note  here  that  these  hybrids 
of  the  hare  and  the  rabbit  are  fertile,  not  only  with 
either  hares  or  rabbits,  but  with  each  other.  Thir- 
teen generations  have  already  been  enumerated, 
and  the  last  remains  so  vigorous  that  no  cessation 
whatever  is  to  be  anticipated. 

In  presence  of  this  case  (and  others,  though  less 
striking,  might  be  named)  there  is  but  one  alterna- 
tive— either  we  must  declare  that  rabbits  and  hares 
form  one  and  the  same  species — which  is  absurd — 
or  we  must  admit  that  new  types  may  be  formed  "by 
the  union  of  two  existing  races ;  and,  consequently, 
that  species  are  variable.  If  the  doctrine  of  fixity 
of  species  acknowledges  the  touchstone  of  hybrid- 
ity,  the  fate  of  the  doctrine  is  settled  forever. 
F 


122  STUDIES  IN  ANIMAL  LIFE. 

Although  I  conceive  the  doctrine  of  fixity  of 
species  to  be  altogether  wrong,  I  can  not  say  that 
the  arguments  adduced  in  favor  of  the  development 
hypothesis  rise  higher  than  a  high  degree  of  proba- 
bility, still  very  far  from  demonstration ;  they  will 
leave  even  the  most  willing  disciple  beset  with  dif- 
ficulties and  doubts.  When  stated  in  general  terms, 
that  hypothesis  has  a  fascinating  symmetry  and 
simplicity ;  but  no  sooner  do  we  apply  it  to  partic- 
ular cases,  than  a  thick  veil  of  mystery  descends, 
and  our  pathway  becomes  a  mere  blind  groping  to- 
ward the  light.  There  is  nothing  but  what  is  per- 
fectly conceivable,  and  in  harmony  with  all  analo- 
gies, in  the  idea  of  all  animal  forms  having  arisen 
from  successive  modifications  of  one  original  form, 
but  there  are  many  things  perfectly  conceivable 
which  have  nevertheless  no  existence ;  there  are 
many  explanations  perfectly  probable  which  are 
not  true ;  and  when  we  come  to  seek  for  the  evi- 
dence of  the  development  hypothesis,  that  evidence 
fails  us.  It  may  be  true,  but  we  can  not  say  that  it 
is  true.  Ten  years  ago  I  espoused  the  hypothesis, 
and  believed  that  it  must  be  the  truth;  but  ten 
years  of  study,  instead  of  deepening,  have  loosened 
that  conviction :  they  have  strengthened  my  oppo- 
sition to  the  hypothesis  of  fixity  of  species,  but 
they  have  given  greater  force  to  the  difficulties 
which  beset  the  development  hypothesis,  and  have 
made  me  feel  that  at  present  the  requisite  evidence 
is  wanting.  I  conclude  with  reminding  the  reader 


STUDIES  IN  ANIMAL  LIFE.  123 

that  the  question  of  the  origin  of  species  is  at  pres- 
ent incapable  of  a  positive  answer ;  of  the  two  hy- 
potheses, that  of  development  seems  the  more  har- 
monious with  our  knowledge;  but  it  is  no  more 
than  an  hypothesis,  and  will  probably  forever  re- 
main one.  Now  an  hypothesis,  although  indispens- 
able as  a  provisional  mode  of  grouping  together 
facts,  and  giving  them  some  sort  of  explanation,  is, 
after  all,  only  a  guess,  and  it  may  be  absurdly  wide 
of  the  truth.  In  Natural  History,  as  in  all  other 
departments  of  speculative  ingenuity,  there  have 
been  a  goodly  number  of  outrageously  extravagant 
hypotheses  gravely  propounded  and  credulously 
accepted.  Men  prefer  an  absurd  guess  to  a  blank ; 
they  would  rather  have  'a  false  opinion  than  no 
opinion ;  and  one  of  the  last  developments  of  phil- 
osophic culture  is  the  power  of  abstaining  from 
forming  an  opinion  where  the  necessary  data  are 
absent. 

If  you  wish  to  see  how  easily  hypotheses  are 
formed  and  accepted,  you  need  only  turn  over  the 
history  of  any  science.  If  you  want  a  laugh  at 
credulity,  read  a  chapter  of  Pliny's  Natural  History. 
Pliny  is  a  classic,  and  was  for  centuries  an  author- 
ity ;  but,  looked  at  with  impartial  eyes,  he  appears 
the  veriest  "  old  woman"  that  ever  wrote  in  a  beau- 
tiful style.  He  was  a  mere  bookworm,  without  a 
particle  of  scientific  insight.  His  was  not  an  age 
when  men  had  much  regard  to  evidence ;  but  to 
him  the  suspicion  never  seems  to  have  occurred 


124  STUDIES  IN  ANIMAL  LIFE. 

that  Gossip  Eeport  could  be  given  to  romancing, 
or  that  travelers  could  "see  strange  things."  No 
fable  is  too  monstrous  for  his  credulity. 

One  of  the  pretty  fables  Pliny  repeats  is  that 
pearls  are  formed  by  drops  of  dew  falling  into  the 
gaping  valves  of  the  oyster.  It  never  occurred  to 
him  to  ask  whether  oysters  were  ever  exposed  to 
the  dew?  whether  the  drops  could  fall  into  their 
valves  ?  whether  oysters  kept  their  valves  open  ex- 
cept when  under  water  ?  or,  finally,  whether,  if  the 
dew  did  fall  in,  it  would  remain  a  rounded  drop  ? 
The  drop  of  dew  had  a  certain  superficial  resem- 
blance to  the  pearl,  and  that  was  enough.  Julian's 
hypothesis  was  somewhat  better :  he  supposed  that 
the  pearls  were  produced  by  lightning  flashing  into 
the  open  shells. 

Turning  from  these  ancient  sages,  you  will  ask 
how  pearls  are  formed  ?  And  almost  any  ingenious 
modern,  not  a  zoologist,  will  tell  you  (and  tell  you 
falsely)  that  the  pearl  is  a  disease  of  the  oyster. 
One  is  somewhat  fatigued  at  the  merciless  frequen- 
cy with  which  this  notion  has  been  dragged  in,  as 
an  illustration  of  genius  issuing  out  of  sorrow  and 
adversity,  and  it  is  time  to  stop  that  "  damnable 
iteration"  by  discrediting  the  notion.  Know  then 
that  if 

"  Most  wretched  men 
Are  cradled  into  poetry  by  wrong, 
They  learn  in  suffering  what  they  teach  in  song"  — 

it  is  not  true  that  oysters  secrete  in  suffering  what 


STUDIES  IN  ANIMAL  LIFE.  125 

women  wear  as  necklaces.  Disease  would  be  the 
very  worst  cradle  for  pearls.  The  idea  of  disease 
originated  in  a  fanciful  supposition  of  pearls  being 
to  the  oyster  and  mussel  what  gall-stones  and  uri- 
nary calculi  are  to  higher  and  more  suffering  ani- 
mals. Keaumur,  to  whom  we  owe  so  many  good 
observations  and  suggestive  ideas,  came  near  the 
truth  when,  in  1717,  he  showed  that  the  structure  of 
pearls  was  identical  with  the  structure  of  the  shells 
in  which  they  grow.  He  attributed  their  formation 
to  the  morbid  effusion  of  coagulating  shell-material. 
I  presume  you  know  that  shells  are  formed  by  a 
secretion  from  the  mantle?  The  mantle  is  that 
delicate  semi-transparent  membrane  which  you  ob- 
serve, on  opening  a  mussel,  lining  the  whole  inte- 
rior of  the  shells,  and  having  at  its  free  margins  a 
sort  of  fringe  of  delicate  tentacles  which  are  sensi- 
tive and  retractile.  A  microscopic  examination  of 
these  fringes  shows  them  to  be  glandular  in  struc- 
ture— that  is,  they  are  secreting  organs.  The  whole 
mantle,  indeed,  is  a  secreting  organ,  and  its  secre- 
tion is  the  shell-material:  the  fringes  secrete  the 
coloring  matters  of  the  shell,  and  enlarge  its  circum- 
ference ;  the  rest  of  the  mantle  secretes  the  nacre, 
or  mother  of  pearl,  and  increases  the  thickness  of 
the  shell.  Now  it  is  obvious  that  the  formation  of 
pearl  nacre  and  of  pearls  depends  on  the  healthy 
condition  of  the  mantle,  not  on  its  diseases.  If  the 
mantle  be  injured,  the  nacre  is  not  secreted  at  all, 
or  in  less  quantities. 


126  STUDIES  IN  ANIMAL  LIFE. 

But,  although  pearls  depend  upon  the  healthy, 
not  the  diseased  activity  of  the  mantle,  it  is  clear 
that  there  must  be  some  unusual  condition  present 
for  their  formation,  since  the  secretion  of  nacre 
does  not  spontaneously  assume  the  form  of  pearls. 
What  is  the  unusual  condition  ?  Naturalists  are  at 
present  divided  into  two  camps,  fighting  vigorously 
for  victory.  The  one  side  maintains  that  the  origin 
of  a  pearl  is  this  :  an  egg  of  the  oyster  has  escaped 
and  strayed  under  the  mantle,  or  the  egg  of  a  para- 
site has  been  deposited  there;  this  egg  forms  the 
nucleus  round  which  the  nacre  forms,  and  thus  we 
have  the  pearl.  The  other  side  maintains  with 
great  positiveness  that  any  thing  will  form  a  nucleus, 
a  grain  of  sand  no  less  than  the  egg  of  a  parasite. 
'Tis  a  pretty  quarrel,  which  we  may  leave  them  to 
settle.  Some  aver  that  grains  of  sand  are  more  nu- 
merous than  any  thing  else ;  but  Mobius  says  that 
of  forty -four  sea  pearls  and  fifteen  fresh-water  pearls 
examined  by  him,  not  one  contained  a  grain  of  sand ; 
and  Filippi,  who  has  extensively  investigated  this 
subject,  denies  that  a  grain  of  sand  ever  forms  the 
nucleus  of  a  true  pearl.  Both  Filippi  and  Kiichen- 
meister*  declare  that  a  parasite  gets  into  the  mussel 
or  oyster,  and  its  presence  there  stimulates  an  active 
secretion  of  nacre. 

There  are  pearls,  according  to  Mobius,  which 
consist  of  three  different  systems  of  layers,  like  the 
shells  in  which  they  are  formed;  with  this  differ- 
*  See  their  interesting  essays  in  MULLER'S  Archiv.,  1856. 


STUDIES  IN  ANIMAL  LIFE.  127 

ence,  that  these  layers  are  reversed;  in  the  shell  the 
nacre  forms  the  innermost  layer,  in  the  pearl  it 
forms  the  outermost.  Hence  the  qualities  of  the 
pearl  depend  on  the  shell,  and  on  the  different  pro- 
portions of  nacre  and  carbonate  of  lime. 

Since  we  know  how  pearls  are  made,  may  it  not 
be  expected  that  we  should  learn  to  make  them  ? 
Ever  since  the  days  of  Linnasus  the  hope  has  been 
entertained,  and  it  is  now  becoming  every  day  more 
likely  to  be  realized.  Imperfect  pearls  have  been 
made  in  abundance.  The  Chinese  have  long  prac- 
ticed the  art.  They  simply  remove  the  large  fresh- 
water mussel  from  the  water,  insert  a  foreign  sub- 
stance under  the  mantle,  and  in  two  or  three  years 
(if  I  remember  rightly)  they  take  the  mussels  up 
again,  and  find  the  pearls  formed.  In  this  way 
they  make  little  mother-of-pearl  Josses,  which  are 
sold  for  a  penny  each;  and  I  remember  seeing  a 
couple  of  large  shells  in  the  Anatomical  Museum  at 
Munich,  the  whole  length  of  which  was  occupied  by 
rows  of  little  squab  Josses,  very  comical  to  behold. 
I  was  informed  that  a  copper  chain  of  these  deities 
had  been  inserted  under  the  mollusk's  mantle,  and 
this  was  the  result. 


128  STUDIES  IN  ANIMAL  LIFE. 


CHAPTER  YI. 

Every  Organism  a  Colony. — What  is  a  Paradox  ? — An  Organ  is 
an  independent  Individual  and  a  dependent  one. — A  Branch 
of  Coral. — A  Colony  of  Polypes. — The  Siphonophora. — Uni- 
versal Dependence. — Youthful  Aspirings. — Our  Interest  in  the 
Youth  of  great  Men. — Genius  and  Labor. — Cuvier's  College 
Life ;  his  Appearance  in  Youth ;  his  Arrival  in  Paris. — Cuvier 
and  Geoffroy  St.Hilaire. — Causes  of  Cuvier's  Success. — One  of 
his  early  Ambitions. — M.  le  Baron. — Omnia  vindt  labor. — Con- 
clusion. 

THAT  an  animal  organism  is  made  up  of  several 
distinct  organs,  and  these  the  more  numerous  in 
proportion  to  the  rank  of  the  animal  in  the  scale  of 
beings,  is  one  of  those  familiar  facts  which  have 
their  significance  concealed  from  us  by  familiarity. 
But  it  is  only  necessary  to  express  this  fact  in  lan- 
guage slightly  altered,  and  to  say  that  an  animal 
organism  is  made  up  of  several  distinct  individuals, 
and  our  attention  is  at  once  arrested.  Doubtless  it 
has  a  paradoxical  air  to  say  so ;  but  Natural  His- 
tory is  full  of  paradoxes ;  and  you  are  aware  that  a 
paradox  is  far  from  being  necessarily  an  absurdity, 
as  some  inaccurate  writers  would  lead  us  to  sup- 
pose ;  the  word  meaning  simply  "  contrary  to  what 
is  thought" — a  meaning  by  no  means  equivalent  to 
"  contrary  to  what  is  the  fact."  It  is  paradoxical 
to  call  an  animal  an  aggregate  of  individuals,  but  it 


STUDIES  IN   ANIMAL  LIFE.  129 

is  so  because  our  thoughts  are  not  very  precise  on 
the  subject  of  individuality — one  of  the  many  ab- 
stractions which  remain  extremely  vague.  To  jus- 
tify this  application  of  the  word  individual  to  every 
distinct  organ  would  be  difficult  in  ordinary  speech, 
but  in  philosophy  there  is  ample  warrant  for  it. 

An  organ,  in  the  physiological  sense,  is  an  instru- 
ment whereby  certain  functions  are  performed.  In 
the  morphological  sense,  it  arises  in  a  differentiation, 
or  setting  apart,  of  a  particular  portion  of  the  body 
for  the  performance  of  particular  functions — a  group 
of  cells,  instead  of  being  an  exact  repetition  of  all 
the  other  cells,  takes  on  a  difference,  and  becomes 
distinguished  from  the  rest  as  an  organ.* 

Combining  these  two  meanings,  we  have  the  third 
or  philosophical  sense  of  the  word,  which  indicates 
that  every  organ  is  an  individual  existence,  depend- 
ent more  or  less  upon  other  organs  for  its  mainte- 
nance and  activity,  yet  biologically  distinct.  I  do 
not  mean  that  the  heart  will  live  independent  of 
the  body — at  least  not  for  long,  although  it  does 
continue  to  live  and  manifest  its  vital  activity  for 
some  time  after  the  animal's  death ;  and,  in  the 
cold-blooded  animals,  even  after  removal  from  the 
body.  Nor  do  I  mean  that  the  legs  of  an  animal 
will  manifest  vivacity  after  amputation,  although 
even  the  legs  of  a  man  are  not  dead  for  some  time 
after  amputation;  and  the  parts  of  some  of  the 
lower  animals  are  often  vigorously  independent. 

*  See  on  this  point  what  was  said  in  our  first  chapter,  p.  22. 

F2 


130  STUDIES  IN  ANIMAL  LIFE. 

Thus  I  have  had  the  long  tentacles  of  a  Terebella  (a 
marine  worm)  living  and  wriggling  for  a  whole 
week  after  amputation.*  In  speaking  of  the  inde- 
pendence of  an  organ,  I  must  be  understood  to  mean 
a  very  dependent  independence;  because,  strictly 
speaking,  absolute  independence  is  nowhere  to  be 
found ;  and,  in  the  case  of  an  organ,  it  is  of  course 
dependent  on  other  organs  for  the  securing,  prepar- 
ing, and  distributing  of  its  necessary  nutriment. 
The  tentacles  of  my  Terebella  could  find  no  nutri- 
ment, and  they  perished  from  the  want  of  it,  as  the 
Terebella  itself  would  have  perished  under  like  cir- 
cumstances. The  frog's  heart  now  beating  on  our 
table  with  such  regular  systole  and  diastole,  as  if  it 
were  pumping  the  blood  through  the  living  animal, 
gradually  uses  up  all  its  force ;  and  since  this  force 
is  not  replaced,  the  beatings  gradually  cease.  A 
current  of  electricity  will  awaken  its  activity  for  a 
time,  but  at  last  every  stimulus  will  fail  to  elicit  a 
response.  The  heart  will  then  be  dead,  and  decom- 
position will  begin. 

Dependent,  therefore,  every  organ  must  be  on 
some  other  organs.  Let  us  see  how  it  is  also  inde- 
pendent ;  and  for  this  purpose  we  glance,  as  usual, 
at  the  simpler  forms  of  life  to  make  the  lesson  easi- 
er. Here  is  a  branch  of  coral,  which  you  know  to 
be  in  its  living  state  a  colony  of  polypes.  Each  of 
these  multitudinous  polypes  is  an  individual,  and 
each  exactly  resembles  the  others.  But  the  whole 

*  Seaside  Studies,  2d  edition,  p.  59  sq. 


STUDIES  IN  ANIMAL  LIFE. 


131 


colony  has  one  nutritive  fluid 

in   common.      They   are   all 

actively  engaged  in  securing 

food,  and  the  labors  of  each 

enrich  all.     It  is  animal  so- 

cialism of  the  purest  kind  — 

there  are  no  rich  and  no  poor, 

neither  are  there  any  idlers. 

Formerly    the    coral  -branch 

was  regarded  as  one  animal 

—  an  individual;  and  a  tree 

was  and  is  commonly  regard- 

ed as  one  plant  —  an  individ- 

ual.    But  no  zoologist  now 

is  unaware  of  the  fact  that 

each  polype  on  the  branch  is 

a  distinct  individual,  in  spite 

of  its  connections  with  the 

rest;    and  philosophic  bota- 

nists  are  agreed  that  the  tree  is  a  colony  of  individ- 

ual plants  —  not  one  plant. 

Let  us  pass  from  the  coral  to  the  stem  of  some 
other  polype,  say  a  Campanularia.  Above  is  the 
representation  of  such  a  stem,  of  the  natural  size, 
and  beside  it  a  tiny  twig  much  magnified.  You 
observe  the  ordinary  polype  issuing  from  one  of  the 
capsules,  and  expanding  its  coronal  of  tentacles  in 
the  water.  The  food  it  secures  will  pass  along  the 
digestive  tract  to  each  of  the  other  capsules.  Un- 
der the  microscope  you  may  watch  this  oscillation 


(mag. 


132  STUDIES  IN  ANIMAL  LIFE. 

of  the  food.  But  your  eye  detects  a  noticeable  dif- 
ference between  this  polype  in  its  capsule,  and  the 
six  semi-transparent  masses  in  the  second  capsule ; 
although  the  two  capsules  are  obviously  identical, 
they  are  not  the  same ;  a  differentiation  has  taken 
place.  Perhaps  you  think  that  six  polypes  are 
here  crowding  into  one  capsule  ?  Error  !  If  you 
watch  with  patience,  or  if  you  are  impatient  yet 
tolerably  dexterous,  you  may  press  these  six  mass- 
es out,  and  then  will  observe  them  swim  away,  so 
many  tiny  jellyfish.  Not  polypes  at  all,  but  jelly- 
fish, are  in  this  capsule ;  and  these,  in  due  time, 
will  produce  polypes,  like  that  one  now  waving 
its  tentacles. 

Having  made  this  observation,  it  will  naturally 
occur  to  you  that  the  polype  stem  which  bore  such 
different  capsules  as  are  represented  by  these  two 
may  perhaps  be  called  a  colony,  but  it  is  a  colony 
of  different  individuals.  While  they  have  all  one 
skeleton  in  common,  nutrition  in  common,  and  res- 
piration in  common,  they  have  at  least  one  differ- 
entiation, or  setting  apart  for  a  particular  purpose, 
and  that  is  the  reproductive  capsule.  This  is  an 
individual  as  much  as  any  of  the  others,  but  it  is  an 
individual  that  does  nothing  for  the  general  good ; 
it  takes  upon  itself  the  care  of  the  race,  and  be- 
comes an  "  organ"  for  the  community  ;  the  others 
feed  it,  and  it  is  absolved  from  the  labor  of  nutri- 
tion as  much  as  the  arm  or  the  brain  of  a  man  are. 

From  this  case,  let  us  pass  to  the  group  of  jelly- 


STUDIES  IN  ANIMAL  LIFE.  133 

fish,  called  Siphonophora  (siphon-bearers)  by  natu- 
ralists, and  we  shall  see  this  union  of  very  differ- 
ent individualities  into  one  inseparable  colony  still 
more  strikingly  exhibited :  there  are  distinct  indi- 
viduals to  feed  the  colony,  individuals  to  float  it 
through  the  water,  individuals  to  act  as  feelers,  and 
to  keep  certain  parts  distended  with  fluid,  and  final- 
ly reproductive  individuals.  All  these  are  identical 
in  origin,  and  differ  only  by  slight  differentiations.* 
Here  we  have  obviously  an  approach  to  the  more 
complex  organism  in  which  various  distinct  organs 
perform  the  several  functions,  only  no  one  calls  the 
organism  a  colony. 

The  individuals  composing  one  of  these  Siphono- 
phora are  so  manifestly  analogous  to  organs,  that 
their  individuality  may  perhaps  be  disputed,  the 
more  so  as  they  do  not  live  separately.  But  the 
gradations  of  separation  are  very  fine.  You  would 
never  hesitate  to  call  a  bee  or  an  ant  an  individual, 
yet  no  bee  or  ant  could  exist  if  separated  from  its 
colony.  So  great  is  the  "  physiological  division  of 
labor"  which  has  taken  place  among  these  insects, 
that  one  can  not  get  food,  another  can  not  feed  it- 
self, but  it  will  fight  for  the  community ;  another 
can  not  work,  but  it  will  breed  for  the  community ; 
another  can  not  breed,  but  it  will  work.  Each  of 

*  Compare  LEUCKART  :  Ueber  den  Polymorpliismus  der  Individ- 
ven.  GEGENBAUR  :  Grundzuge  der  Vergleichende  Anatomie ;  and 
HUXLEY'S  splendid  monograph  on  the  Oceanic  Hydrozoa,  published 
by  the  Ray  Society. 


134  STUDIES  IN  ANIMAL  LIFE. 

these  is  little  more  than  separated  organs  of  the 
great  insect  organism,  as  the  heart,  stomach,  and 
brain  are  united  organs  of  the  human  organism. 
Eemove  one  of  these  insects  from  the  community, 
and  it  will  soon  perish,  for  its  life  is  bound  up  with 
the  whole. 

And  so  it  is  every  where ;  the  dependence  is  uni- 
versal : 

"  Nothing  in  this  world  is  single, 

All  things,  by  a  law  divine, 
In  one  another's  being  mingle." 

We  are  dependent  on  the  air,  the  earth,  the  sun- 
light, the  flowers,  the  plants,  the  animals,  and  all 
created  things,  directly  or  indirectly.  Nor  is  the 
moral  dependence  less  than  the  physical.  "We  can 
not  isolate  ourselves  if  we  would.  The  thoughts 
of  others,  the  sympathies  of  others,  the  needs  of 
others — these  too  make  up  our  life ;  without  these 
we  should  quickly  perish. 

It  was  a  dream  of  the  youth  Cuvier  that  a  His- 
tory of  Nature  might  be  written  which  would  sys- 
tematically display  this  universal  interdependence. 
I  know  few  parts  of  biography  so  interesting  as 
those  which  show  us  great  men  in  their  early  aspir- 
ings, when  dreams  of  achievements  vaster  than 
the  world  has  seen  fill  their  souls  with  energy  to 
achieve  the  something  they  do  afterward  achieve. 
It  is,  unhappily,  too  often  but  the  ambition  of  youth 
we  have  to  contemplate;  and  yet  the  knowledge 
that  after-life  brought  with  it  less  of  hope,  less  of 


STUDIES  IN  ANIMAL  LIFE.  135 

devotion,  and  less  of  generous  self-sacrifice,  renders 
these  early  days  doubly  interesting.  Let  the  abate- 
ment of  high  hopes  come  when  it  may,  the  exist- 
ence of  an  aspiration  is  itself  important.  I  have 
been  lately  reading  over  again  the  letters  of  Cuvier 
when  an  obscure  youth,  and  they  have  given  me 
quite  a  new  feeling  with  regard  to  him. 

There  is  a  good  reason  why  novels  always  end 
with  the  marriage  of  the  hero  and  heroine ;  our  in- 
terest is  always  more  excited  by  the  struggles  than 
by  the  results  of  victory.  So  long  as  the  lovers 
are  unhappy  or  apart,  and  are  eager  to  vanquish 
obstacles,  our  sympathy  is  active;  but  no  sooner 
are  they  happy,  than  we  begin  to  look  elsewhere 
for  other  stragglers  on  whom  to  bestow  our  inter- 
est. It  is  the  same  with  biography.  We  follow 
the  hero  through  the  early  years  of  struggle  with 
intense  interest,  and  as  long  as  he  remains  unsuc- 
cessful, baffled  by  rivals  or  neglected  by  the  world, 
we  stand  by  him  and  want  him  to  succeed ;  but  the 
day  after  he  is  recognized  by  the  world  our  sym- 
pathy begins  to  slacken. 

It  is  this  which  gives  Cuvier's  Letters  to  Pfaff* 
their  charm.  I  confess  that  M.  le  Baron  Cuvier, 
administrator,  politician,  academician,  professor,  dic- 
tator, has  always  had  but  a  very  tepid  interest  for 
me,  probably  because  his  career  early  became  a,  con- 
tinuous success,  and  Europe  heaped  rewards  upon 

*  Lettres  de  Georges  Cuvier  a  C.  M.  Pfaff,  1788-92.  Traduites 
de  1'Allemand,  par  Louis  Marchant,  1858. 


136  STUDIES  IN  ANIMAL  LIFE. 

him ;  whereas  his  unsuccessful  rival,  Geoffrey  St. 
Hilaire,  claims  my  sympathy  to  the  close.  If,  how- 
ever, M.  le  Baron  is  a  somewhat  dim  figure  in  my 
biographical  gallery,  it  is  far  otherwise  with  the 
youth  Cuvier  as  seen  in  his  letters ;  and  as  at  this 
present  moment  there  is  nothing  under  our  micro- 
scope which  can  seduce  us  from  the  pleasant  vol- 
ume, suppose  we  let  our  "  studies"  take  a  biograph- 
ical direction? 

" Genius,"  says  Carlyle,  "means  transcendent  ca- 
pacity for  taking  trouble,  first  of  all."  There  are 
many  young  gentlemen  devoutly  persuaded  of  their 
own  genius,  and  yet  candidly  avowing  their  im- 
perfect capacity  for  taking  trouble,  who  will  vehe- 
mently protest  against  this  doctrine.  Without  dis- 
cussing it  here,  let  us  say  that,  genius  or  no  genius, 
success  of  any  value  is  only  to  be  purchased  by  im- 
mense labor :  and  in  science,  assuredly,  no  one  will 
expect  success  without  first  paying  this  price.  In 
Cuvier's  history  may  be  seen  what  "  capacity  for 
taking  trouble"  was  required  before  his  success 
could  be  achieved ;  and  this  gives  these  Lettres  d 
Pfaff  a  moral  as  well  as  an  interest. 

It  was  in  the  Eittersaal  of  the  Academia  Carolina 
of  Stuttgardt  that  Pfaff,  the  once  famous  supporter 
of  Yolta,  and  in  1787  the  fellow-student  of  Cuvier, 
first  became  personally  acquainted  with  him.  Al- 
though they  had  been  three  years  together  at  the 
same  university,  the  classification  of  students  there 
adopted  had  prevented  any  personal  acquaintance. 


STUDIES  IN  ANIMAL  LIFE.  137 

Pupils  were  admitted  at  the  age  of  nine,  and  com- 
menced their  studies  with  the  classic  languages. 
Thence  they  passed  to  the  philosophical  class,  and 
from  that  they  went  to  one  of  the  four  faculties — 
Law,  Medicine,  Administration,  and  Military  Sci- 
ence. Each  faculty,  of  course,  was  kept  distinct ; 
and  as  Pfaff  was  studying  philosophy  at  the  time 
Cuvier  was  occupied  with  the  administrative  sci- 
ences, they  never  met,  the  more  so  as  the  dormito- 
ries and  hours  of  recreation  were  different.  The 
academy  was  organized  on  military  principles.  The 
three  hundred  students  were  divided  into  six  classes, 
two  of  which  comprised  the  nobles,  and  the  other 
four  the  bourgeoisie.  Each  of  these  classes  had  its 
own  dormitory,  and  was  placed  under  the  charge 
of  a  captain,  a  lieutenant,  and  two  inferior  officers. 
These  six  classes,  in  which  the  students  were  enter- 
ed according  to  their  age,  size,  and  time  of  admis- 
sion, were  kept  separate  in  their  recreations  as  in 
their  studies.  But  those  of  the  students  who  par- 
ticularly distinguished  themselves  in  the  public  ex- 
aminations were  raised  to  the  rank  of  knights,  and 
had  a  dormitory  to  themselves,  besides  dining  at 
the  same  table  with  the  young  princes  who  were 
then  studying  at  the  university.  Pfaff  and  Cuvier 
were  raised  to  this  dignity  at  the  same  time,  and 
here  commenced  their  friendship. 

What  a  charm  there  is  in  school  friendships, 
when  youth  is  not  less  eager  to  communicate  its 
plans  and  hopes  than  to  believe  in  the  plans  and 


138  STUDIES  IN  ANIMAL  LIFE. 

hopes  of  others ;  when  studies  are  pursued  in  com- 
mon, opinions  frankly  interchanged,  and  the  supe- 
riority of  a  friend  is  gladly  acknowledged,  even  be- 
coming a  source  of  pride,  instead  of  being,  as  in  aft- 
er years,  a  thorn  in  the  side  of  friendship !  This 
charm  was  felt  by  Cuvier  and  Pfaff,  and  a  small 
circle  of  fellow-students  who  particularly  devoted 
themselves  to  Natural  History.  They  formed  them- 
selves into  a  society,  of  which  Cuvier  drew  up  the 
statutes  and  became  the  president.  They  read  mem- 
oirs, and  discussed  discoveries  with  all  the  gravity 
of  elder  societies,  and  even  published,  among  them- 
selves, a  sort  of  Comptes  Rendus.  They  made  bo- 
tanical, entomological,  and  geological  excursions ; 
and,  still  further  to  stimulate  their  zeal,  Cuvier  in- 
stituted an  Order  of  Merit,  painting  himself  the  me- 
dallion: it  represented  a  star,  with  the  portrait  of 
Linnaeus  in  the  centre,  and  between  the  rays  vari- 
ous treasures  of  the  animal  and  vegetable  world. 
And  do  you  think  these  boys  were  not  proud  when 
their  president  awarded  them  this  medal  for  some 
happy  observation  of  a  new  species,  or  some  well- 
considered  essay  on  a  scientific  question  ? 

At  this  period  Cuvier's  outward  appearance  was 
as  unlike  M.  le  Baron  as  the  grub  is  unlike  the 
butterfly.  Absorbed  in  his  multifarious  studies, 
he  was  careless  about  disguising  the  want  of  ele- 
gance in  his  aspect.  His  face  was  pale,  very  thin 
and  long,  covered  with  freckles,  and  encircled  by  a 
shock  of  red  hair.  His  physiognomy  was  severe 


STUDIES  IN  ANIMAL  LIFE.  139 

and  melancholy.  He  never  played  at  any  of  the 
boys'  games,  and  seemed  as  insensible  of  all  that 
was  going  on  around  him  as  a  somnambulist.  His 
eye  seemed  turned  inward;  his  thoughts  moved 
amid  problems  and  abstractions.  Nothing  could 
exceed  the  insatiable  ardor  of  his  intellect.  Besides 
his  special  administrative  studies,  he  gave  himself 
to  Botany,  Zoology,  Philosophy,  Mathematics,  and 
the  history  of  literature.  No  work  was  too  volu- 
minous or  too  heavy  for  him.  He  was  reading  all 
day  long,  and  a  great  part  of  the  night.  "I  re- 
member well,"  says  Pfaff,  "  how  he  used  to  sit  by 
my  bedside  going  regularly  through  Bayle's  Dic- 
tionary. Falling  asleep  over  my  own  book,  I  used 
to  awake  after  an  hour  or  two,  and  find  him  mo- 
tionless as  a  statue,  bent  over  Bayle."  It  was  dur- 
ing these  years  that  he  laid  the  basis  of  that  exten- 
sive erudition  which  distinguished  his  works  in 
after  life,  and  which  is  truly  remarkable  when  we 
reflect  that  Cuvier  was  not  in  the  least  a  bookworm, 
but  was  one  of  the  most  active  workers,  drawing  his 
knowledge  of  details  from  direct  inspection  when- 
ever it  was  possible,  and  not  from  the  reports  of 
others.  It  was  here,  also,  that  he  preluded  to  his 
success  as  a  professor,  astonishing  his  friends  and 
colleagues  by  the  clearness  of  his  exposition,  which 
he  rendered  still  more  striking  by  his  wonderful 
mastery  with  the  pencil.  One  may  safely  say  that 
there  are  few  talents  which  are  not  available  in 
Natural  History ;  a  talent  for  drawing  is  pre-emi- 


140  STUDIES  IN  ANIMAL  LIFE. 

nently  useful,  since  it  not  only  enables  a  man  to 
preserve  observations  of  fugitive  appearances,  but 
sharpens  his  faculty  of  observation  by  the  exercise 
it  gives.  Cuvier's  facile  pencil  was  always  em- 
ployed: if  he  had  nothing  to  draw  for  his  own 
memoirs  or  those  of  his  colleagues,  he  amused  him- 
self with  drawing  insects  as  presents  to  the  young 
ladies  of  his  acquaintance — an  entomologist's  gal- 
lantry, which  never  became  more  sentimental. 

In  1788,  that  is,  in  his  nineteenth  year,  Cuvier 
quitted  Stuttgardt,  and  became  tutor  in  a  noble- 
man's family  in  Normandy,  where  he  remained  till 
1795,  when  he  was  discovered  by  the  Abbe  Tessier, 
who  wrote  to  Parmentier,  "  I  have  just  found  a 
pearl  in  the  dunghill  of  Normandy :"  to  Jussieu.  he 
wrote,  "  Kemember  it  was  I  who  gave  Delambre  to 
the  academy ;  in  another  department  this  also  will 
be  a  Delambre."  Geoffroy  St.  Hilaire,  already  pro- 
fessor at  the  Jardin  des  Plantes,  though  younger 
than  Cuvier,  was  shown  some  of  Cuvier's  manu- 
scripts, which  filled  him  with  such  enthusiasm  that 
he  wrote  to  him,  "  Come  and  fill  the  place  of  Lin- 
naeus here ;  come  and  be  another  legislator  of  nat- 
ural history."  Cuvier  came,  and  Geoffroy  stood 
aside  to  let  his  great  rival  be  seen. 

Goethe,  as  I  have  elsewhere  remarked,  has  no- 
ticed the  curious  coincidence  of  the  three  great  zo- 
ologists successively  opening  to  their  rivals  the  path 
to  distinction :  Buffon  called  Daubenton  to  aid  him ; 
Daubenton  called  Geoffroy;  and  Geoffroy  called 


STUDIES  IN  ANIMAL  LIFE.  141 

Cuvier.  Goethe  further  notices  that  there  was  the 
same  radical  opposition  in  the  'tendencies  of  Buffon 
and  Daubenton  as  in  those  of  Geoffroy  and  Cuvier 
— the  opposition  of  the  synthetical  and  the  analyt- 
ical mind.  Yet  this  opposition  did  not  prevent 
mutual  esteem  and  lasting  regard.  Geoffroy  and 
Cuvier  were  both  young,  and  had  in  common  am- 
bition, love  of  science,  and  the  freshness  of  unform- 
ed convictions.  For,  alas !  it  is  unhappily  too  true, 
that  just  as  the  free  communicativeness  of  youth 
gives  place  to  the  jealous  reserve  of  manhood,  and 
the  youth  who  would  only  be  too  pleased  to  tell  all 
his  thoughts  and  all  his  discoveries  to  a  companion 
would  in  after  years  let  his  dearest  friend  first  see  a 
discovery  in  an  official  publication,  so  likewise,  in 
the  early  days  of  immature  speculation,  before  con- 
victions have  crystallized  enough  to  present  their 
sharp  angles  of  opposition,  friends  may  discuss  and 
interchange  ideas  without  temper.  Geoffroy  and 
Cuvier  knew  no  jealousy  then.  In  after  years  it 
was  otherwise. 

Geoffroy  had  a  position — he  shared  it  with  his 
friend;  he  had  books  and  collections — they  were 
open  to  his  rival ;  he  had  a  lodging  in  the  museum 
— it  was  shared  between  them.  Daubenton,  older 
and  more  worldly  wise,  warned  Geoffroy  against  this 
zeal  in  fostering  a  formidable  rival,  and  one  day 
placed  before  him  a  copy  of  Lafontaine  open  at  the 
fable  of  The  Bitch  and  her  Neighbor.  But  Geoffroy 
was  not  to  be  daunted,  and  probably  felt  himself 


142  STUDIES  IN  ANIMAL  LIFE. 

strong  enough  to  hold  his  own.  And  so  the  two 
happy,  active  youths  pursued  their  studies  together, 
wrote  memoirs  conjointly,  discussed,  dissected,  spec- 
ulated together,  and  "  never  sat  down  to  breakfast 
without  having  made  a  fresh  discovery,"  as  Cuvier 
said  truly  enough,  for  to  them  every  step  taken  was 
a  discovery. 

Cuvier  became  almost  immediately  famous  on  his 
arrival  at  Paris,  and  his  career  henceforward  was 
one  uninterrupted  success.  Those  who  wish  to 
gain  some  insight  into  the  causes  of  this  success 
should  read  the  letters  to  Pfaff,  which  indicate  the 
passionate  patience  of  his  studies  during  the  years 
1788-1795,  passed  in  obscurity  on  the  Norman 
coast.  Every  animal  he  can  lay  hands  on  is  dis- 
sected with  the  greatest  care,  and  drawings  are 
made  of  every  detail  of  interest.  Every  work  that 
is  published  of  any  note  in  his  way  is  read,  ana- 
lyzed, and  commented  on.  Lavoisier's  new  system 
of  chemistry  finds  in  him  an  ardent  disciple.  Kiel- 
meyer's  lectures  open  new  vistas  to  him.  The  mar- 
vels of  marine  life,  in  those  days  so  little  thought 
of,  he  studies  with  persevering  minuteness  and  with 
admirable  success.  He  dissects  the  cuttlefish,  and 
makes  his  drawings  of  it  with  its  own  ink.  He 
notes  minute  characters  with  the  patience  of  a  spe- 
cies-monger, whose  sole  ambition  is  to  affix  his 
name  to  some  trifling  variation  of  a  common  form, 
yet  with  this  minuteness  of  detail  he  unites  the  large- 
ness of  view  necessary  to  a  comparative  anatomist. 


STUDIES  IN  AN 

"  Your  reflections  on  the  diffe 
mals  and  plants,"  he  writes,  t;  in  the  passage  to 
which  I  previously  referred,  will  be  the  more  agree- 
able to  me,  because  I  am  at  present  working  out  a 
new  plan  of  a  general  natural  history.  I  think  we 
ought  carefully  to  seek  out  the  relation  of  all  exist- 
ences with  the  rest  of  nature,  and,  above  all,  to  show 
their  part  in  the  economy  of  the  great  All.  In  this 
work  I  should  desire  that  the  investigator  should 
start  from  the  simplest  things,  such  as  air  and  wa- 
ter, and  after  having  spoken  of  their  influence  on 
the  whole,  he  should  pass  gradually  to  the  com- 
pound minerals,  from  these  to  plants,  and  so  on; 
and  that  at  each  stage  he  should  ascertain  the  exact 
degree  of  composition,  or,  which  is  the  same  thing, 
the  number  of  properties  it  presents  over  and  above 
those  of  the  preceding  stage,  the  necessary  effects 
of  these  properties,  and  their  usefulness  in  creation. 
Such  a  work  is  yet  to  be  executed.  The  two  works 
of  Aristotle,  De  Historia  Animalium,  and  De  Parti- 
lus  Animalium,  which  I  admire  more  each  time  that 
I  read  them,  contain  a  part  of  what  I  desire,  name- 
ly, the  comparison  of  species,  and  many  of  the  gen- 
eral results.  It  is,  indeed,  the  first  scientific  essay 
at  a  natural  history.  For  this  reason  it  is  necessa- 
rily incomplete,  contains  many  inaccuracies,  and  is 
too  far  removed  from  a  knowledge  of  physical  laws." 
He  passes  on  from  Aristotle  to  Pliny,  Theophrastus, 
Dioscorides,  Aldovrandus,  Gesner,  Gaspar  Bauhin, 


144  STUDIES  IN  ANIMAL  LIFE. 

and  Kay,  rapidly  sketching  the  history  of  natural 
history  as  a  science,  and  concluding  with  this  criti- 
cism on  these  attempts  at  a  nomenclature  which 
neglected  real  science:  " These  are  the  dictionaries 
of  natural  history ;  but  when  will  the  language  be 
spoken  ?" 

No  one  who  reads  these  letters  attentively  will 
be  surprised  at  the  young  Cuvier's  taking  eminent 
rank  among  the  men  of  science  in  France ;  and 
Pfaff,  on  arriving  in  Paris  six  years  afterward, 
found  his  old  fellow-student  had  become  "  a  per- 
sonage." The  change  in  Cuvier's  appearance  was 
very  striking.  He  was  then  at  his  maturity,  and 
might  pass  for  a  handsome  man.  His  shock  of  red 
hair  was  now  cut  and  trimmed  in  Parisian  style; 
his  countenance  beamed  with  health  and  satisfac- 
tion ;  his  expression  was  lively  and  engaging ;  and, 
although  the  slight  tinge  of  melancholy  which  was 
natural  to  him  had  not  wholly  disappeared,  yet  the 
fire  and  vivacity  of  his  genius  overcame  it.  His 
dress  was  that  of  the  fashion  of  the  day,  not  with- 
out a  little  affectation.  Yet  his  life  was  simple, 
and  wholly  devoted  to  science.  He  had  a  lodg- 
ing in  the  Jardin  des  Plantes,  and  was  waited  on 
by  an  old  housekeeper,  like  any  other  simple  pro- 
fessor. 

On  Pfaff 's  subsequent  visit  things  were  changed. 
Instead  of  the  old  housekeeper,  the  door  was  open- 
ed by  a  lackey  in  grand  livery.  Instead  of  asking 


STUDIES   IN  ANIMAL   LIFE.  145 

for  "  Citizen  Cuvier,"  lie  inquired  for  Monsieur  Cu- 
vier ;  whereupon  the  lackey  politely  asked  whether 
he  wished  to  see  M.  le  Baron  Cuvier,  or  M.  Frede- 
ric, his  brother ?  "I  soon  found  where  I  was,'' 
continues  Pfaff.  "  It  was  the  baron,  separated  from 
me  by  that  immense  interval  of  thirty  years,  and  by 
those  high  dignities  which  an  empire  offers  to  the 
ambition  of  men."  He  found  the  baron  almost 
exclusively  interested  in  politics,  and  scarcely  giv- 
ing a  thought  to  science.  The  "  preparations"  and 
"injections"  which  Pfaff  had  brought  with  him 
from  Germany  as  a  present  to  Cuvier  were  scarce- 
ly looked  at,  and  were  set  aside  with  an  indifferent 
"  that's  good,"  and  "  very  fine ;"  much  to  Pfaff's 
distress,  who  doubtless  thought  the  fate  of  the  Mar- 
tignac  ministry  an  extremely  small  subject  of  in- 
terest compared  with  these  injections  of  the  lym- 
phatics. 

But  it  is  not  my  purpose  to  paint  Cuvier  in  his 
later  years.  It  is  to  the  studies  of  his  youth  that  I 
would  call  your  attention,  to  read  there,  once  again, 
the  important  lesson  that  nothing  of  any  solid  value 
can  be  achieved  without  entire  devotion.  Nothing 
is  earned  without  sweat  of  the  brow.  Even  the 
artist  must  labor  intensely.  What  is  called  "in- 
spiration" will  create  no  works,  but  only  irradiate 
works  with  felicitous  flashes ;  and  even  inspiration 
mostly  comes  in  moments  of  exaltation  produced 
by  intense  work  of  the  mind.  In  science,  incessant 


146  STUDIES  IN   ANIMAL   LIFE. 

and  enlightened  labor  is  necessary,  even  to  the 
smallest  success.  Labor  is  not  all ;  but  without  it 
genius  is  nothing. 

With  this  homily,  dear  reader,  may  be  closed  our 
FIRST  SERIES  of  Studies ;  to  be  resumed  hereafter, 
let  me  hope,  with  as  much  willingness  on  your  part 
as  desire  to  interest  you  on  mine. 


THE   END. 


A  LIST  OF  BOOKS. 

PUBLISHED  BY 

HARPER  &  BROTHERS,  Franklin  Square,  N.Y. 

LORD  ELGIN'S  MISSION  TO  CHINA,  &c. 

Narrative  of  Lord  Elgin's  Mission  to  China  and  Japan  in  1857, 
'58,  '59.  Ly  LAURENCE  OLIPHANT,  Secretary  to  Lord  Elgin.  Il- 
lustrations. 8vo,  Muslin,  $2  75. 

OLD  LEAVES. 

Old  Leaves :  Gathered  from  Household  Words.  By  W.  HENRY 
WILLS.  12mo,  Muslin,  $1  00. 

HORACE. 

Horatius,  ex  recensione  A.  J.  MACLEANE,  A.M.  18mo,  Flexible 
Binding,  40  cents. 

^SCHYLUS. 

-<Eschylus,  ex  novissima  recensione  F.  A.  PALET,  A.M.  18mo, 
Flexible  Binding,  40  cents. 

THE  CAXTONS. 

A  Family  Picture.  By  Sir  EDWARD  BULWER  LTTTON,  Bart.  Li- 
brary Edition.  12mo,  Muslin. 

SQUIER'S  NICARAGUA. 

Nicaragua :  Its  People,  Scenery,  Monuments,  Resources,  Condi- 
tions, and  proposed  Canal.  With  One  Hundred  Maps  and  Illustra- 
tions. By  E.  G.  SQUIER,  formerly  Charge  d' Affaires  of  the  United 
States  to  the  Republics  of  Central  America.  A  Revised  Edition. 
Maps  and  Illustrations.  8vo,  Muslin.  (Just  Ready. ) 


2  HARPER  &  BROTHERS' 

HARPER'S  SCHOOL  AND  FAMILY  READERS. 

Harper's  Series  of  School  and  Family  Readers.  By  MARCIUS 
WILLSON. 

flj^TThe  Primer  and  first  Four  Readers  are  now  passing  through 
the  Press.  All  are  splendidly  Illustrated.  The  Prices  will  be  an- 
nounced shortly. 

LUCY  CROFTON. 

By  the  Author  of  "  Margaret  Maitland,"  "  The  Laird  of  Norlaw," 
"The  Days  of  My  Life,"  &c.,  &c.  12mo,  Muslin,  75  cents* 

LIFE  AND  TIMES  OF  GEN.  SAM.  DALE, 

The  Mississippi  Partisan.  By  J.  F.  H.  CLAIBORNE.  Illustrated 
by  JOHN  MCLENAN.  12mo,  Muslin,  $1  00. 

LIFE  IN  SPAIN: 

Past  and  Present.  By  WALTER  THORNBURT.  With  Illustrations. 
12mo,  Muslin,  $1  00. 

SELF-HELP; 

With  Illustrations  of  Character  and  Conduct.  By  SAMUEL  SMILES  , 
Author  of  "  The  Life  of  George  Stephenson."  12mo,  Muslin,  75 
cents. 

PREACHERS  AND  PREACHING. 

By  KIRWAN,  Author  of  "Letters  to  Bishop  Hughes,"  "Roman- 
ism at  Home,"  "Men  and  Things  in  Europe,"  &c.,  &c.  12mo, 
Muslin,  75  cents. 

THE  VIRGINIANS. 

A  Tale  of  the  Last  Century.  By  W.  M.  THACKERAY,  Author  of 
"The  Newcomes,"  "Vanity  Fair,"  "Pendennis,"  &c.,  &c.  With 
Illustrations  by  the  Author.  8vo,  Paper,  $1  95 ;  Muslin.  $2  00. 


